Name: Bo Hellsing.
Date of birth: 20 July 1952.
Nationality: Swedish.
Marital status: Married to Lena, four children Mikko, David, Rut and Ida.
Present address:
Department of Physics
Göteborg University
S-412 96 Göteborg, SWEDEN.
Telephone: + 46-31-7869176
E-mail: hellsing@physics.gu.se
Website: [http://physics.gu.se/~hellsing]
EDUCATIONAL BACKGROUND
Master of Science in Engineering Physics.
Chalmers University of Technology, Göteborg, SWEDEN 1978.
Doctor degree in Theoretical Physics.
Chalmers University of Technology, Göteborg, SWEDEN 1984.
Title of thesis:“Electronic damping of adsorbate motion on metals”.
Docent degree (Honorary Research Associate) in Theoretical Physics.
Chalmers University of Technology, Göteborg, SWEDEN 1991.
Professor in Physics,
Göteborg University of, Göteborg, SWEDEN, 1 April 2003.
EMPLOYMENT
Teaching Assistant,
Institute of Theoretical Physics,
Chalmers University of Technology, Göteborg, SWEDEN 1978-1984.
Post Doctoral position,
Department of Chemistry,
University of California Santa Barbara,
Santa Barbara California, USA, 1985-1986.
Research Assistant (forskningsass.),
Department of Physics,
Chalmers University of Technology, Göteborg, SWEDEN, 1986-1990.
Research Assistant (forskarass.),
Institute of Theoretical Physics,
Chalmers University of Technology, Göteborg, SWEDEN, 1989-94.
University Lecturer (Universitets Lektor),
Department of Physics,
Chalmers University of Technology, Göteborg, SWEDEN, 1994-.
Professor in Physics,
Göteborg University of, Göteborg, SWEDEN, 1 April 2003.
REFERENCES
Prof. Bengt I. Lundqvist,
Department of Applied Physics, Chalmers University of Technology,
S-412 96 Göteborg, SWEDEN.Prof. Bengt Kasemo,
Department of Applied Physics, Chalmers University of Technology,
S-412 96 Göteborg, SWEDEN.Prof. Horia Metiu,
Department of Chemistry, University of California Santa Barbara, CA 93106, USA.Prof. Lars Walldén,
Physics Department, Chalmers University of Technology,
S-412 96 Göteborg, SWEDEN.Prof. Pedro Echenique,
Donostia International Physics Center,
San Sebastian, SPAIN.
FIELDS OF TEACHING EXPERIENCE
Classical Mechanics undergrad. level (Teaching Ass.)
Applied Quantum Mechanics undergrad. level (Teaching Ass.)
Classical Electrodynamics grad. level (Teaching Ass.)
Experimental Laborations undergrad. level (Laboration Ass.)
Mathematics undergrad. level (Lecturing)
Mathematical Physics undergrad. level (Teaching Ass.)
Mathematical Physics undergrad. level (Lecturing)
Solid State Physics undergrad. level (Lecturing)
Statistical Mechanics and
Thermodynamics undergrad. level (Teaching Ass.)
Statistical Mechanics and undergrad. level (Lecturing)
Theoretical Surface Science grad. level (Lecturing)
Quantum Mechanics undergrad. level (Lecturing)
undergrad. level (Teaching Ass.)
grad. level (Teaching Ass.)
PEDAGOGICAL DEVELOPMENT
Course: “Forskarahandledning som profession” 13-14 March 1995
Conference: “Konferens om lärarutbildningen på GU” 19-20 April 1999
Conference: “Konferens om kvalitet och förbättringsarbete”
Luleå 10-11 June 1998,
Oral presentation “Dialog in a creative environment”Course: “Handledning av forskarstuderande” 18-19 November 2004
TEACHING EXPERIENCE
90⁄91 ——————————-
Theoretical Surface Science grad. level (Lecturing)
In this course me, Bengt Lundqvist and Mats Persson gave three 2 hours lectures each, on topics of current interest in the field of theoretical surface science. I gave an overview of “up to date” theoretical tools, for the study of charge transfer processes in molecule-surface scattering.
91⁄92 ——————————-
Quantum Mechanics undergrad. level (Lecturing)
In this Quantum Mechanics introduction course, FY0110, I gave regular lectures and demonstrated solutions to problems. In addition, I introduced mini projects to this course. The results of these projects were presented in seminar form by the students by the end of the course.
Classical Mechanics undergrad. level (Teaching Ass.)
Problem solving and discussions in a small group of 4 students.
Experimental Problem solving undergrad. level (Laboration Ass.)
92⁄93 ——————————-
Theoretical Surface Science grad. level (Lecturing)
The course was completely reorganized this year. In addition to regular lectures, I presented (i) 9 Home problems and (ii) 7-8 Mini-Calculation-Projects (MCP) to the students. For each MCP I supplied a computer program package for studying the specific problem. The fields covered by the MCP:s are: (i) Molecule surface scattering, (ii) Cluster calculation of a chemisorption system and (iii) Kinetic modeling of a surface reaction. Specific problems was formulated which require, (i) a qualitative understanding of the computer program, (ii) variation of input parameters for the investigation, (iii) making conclusions and finally (iv) presentation of the result in a short seminar. The aim was to make the students familiar with performing, and extracting information from, a typical surface science model calculation, and also to make conclusions and organize a presentation of the results. 8 students took part in the course and by the end of 1993, 6 of them have completed the course.
Classical Mechanics undergrad. level (Teaching Ass.)
Problem solving and discussions in a small group of 8 students.
93⁄94 ——————————-
Master Program
During this year I am the personal tutor for the Master student Marcus Preinfalk (MP) from Austria. As he was the single master student on the master program: Physics and Engineering Physics 1993-94 (PEP), the program was not initiated. Together with MP, I constructed a program containing 12 courses, which could meet up with the requirements for a Master degree in PEP. The temporary program was accepted by the local authorities of the department. During the year we have met 1-2 hours 2-3 times a week to discuss problems with courses or any other question related to his program.
Mathematics undergrad. level (Lecturing and problems)
During the spring of 1994 I am lecturing in mathematics at the Halmstad University in Halmstad. During Jan-May I have approximately 180 hours in class, which corresponds to 90 % of a Lecturer position (200 hours for half a year). I am responsible for four courses, (i) Single variable analysis, (ii) Transform theory, (iii) Discrete mathematics and (iv) Linear algebra.
94⁄95 ——————————-
Mathematics undergrad. level (Lecturing, problems and computer projects)
In the fall of 1994 I am responsible for a new course “Mathematical Methods”, which is part of the new Master program at the University of Halmstad. The course is to be runned in parallel with a course “Fotonics”, which will mainly give an insight to Lasers and Fiber optics. The “Mathematical Methods” course I am developing has three components (i) Regular lectures, (ii) Problem solving and (iii) Computer projects. Areas of both mathematics and physics will be included in the course, such as (i) Vector analysis, (ii) Electro magnetic field theory, (iii) Light interaction with matter (classical and quantum picture) and (iv) Theory of Lasers and Fiber optics.
95⁄96 ——————————-
Thermodynamics undergrad. level (Lecturing)
Electricity undergrad. level (Lecturing)
Wave Propagation and Modern Physics undergrad. level (Lecturing)
Those three courses (FYL200) was given for students studying to become teachers in elementary and high school. Home problems were continuously presented in order to keep an even activity during the Thermodynamic and Wave course. I tested a new activity in the Thermodynamic course by presenting a list of every-day phenomena and asked for a 5 minute presentation by each student. This worked out well. By the end of each lecture occasion there was a short talk by a student, which improved the atmosphere in the group.
Energy Physics undergrad. level (Lecturing)
By the fall of 95 I joined the group of physics and mathematics teachers planning the new university program; “Naturvetenskaplig Problemlösning” (“Problem solving in Natural Sciences”). The aim was to try out a fundamentally different approach to teaching and learning. The basic idea is that real learning is connected with your own activity. The amount of traditional lecturing is kept at a lower level, while projects and problem solving is the dominant part.
During the spring of 96 I gave the course “Energy Physics” (14p), which spanned over the hole semester and covered; thermodynamics (part A) and Energy Sources (part B). In part A, student presented solutions to problems and worked with a major numerical computational problem. In part B we worked with 4 themes; Nuclear energy (ii), Mechanical energy, (iii) Solar energy and (iv) Fossil energy and new technologies. During the 4 themes, the students worked in five groups with different aspects, (1) physics, (2) environment effects, (3) new technologies, (4) resources and (5) energy quality. Every group made one “advanced” visit (studiebesök); (1) nuclear power plant (2) Fluidiced combustion plant (3) Wind power plant (4,5) Solar energy plants. All group work, including the visits, was summarized in short oral and written presentations.
96⁄97 ——————————————————–
Thermodynamics undergrad. level (Lecturing)
Electricity undergrad. level (Lecturing)
Wave Physics and Modern Physics undergrad. level (Lecturing and problem solving)
Energy Physics undergrad. level (Lecturing)
97⁄98 ——————————————————-
Thermodynamics undergrad. level (Lecturing and problem solving)
Mechanics undergrad. level (Lecturing)
Wave Physics and Modern Physics undergrad. level (Lecturing and problem solving)
Energy Physics undergrad. level (Lecturing)
98⁄99 ——————————————————-
Mechanics undergrad. level (Lecturing)
Wave Physics and Modern Physics undergrad. level (Lecturing and problem solving)
Energy Physics undergrad. level (Lecturing)
99⁄00 ———————————————————-
Mechanics undergrad. level (Lecturing and problem solving)
Wave Physics and Modern Physics undergrad. level (Lecturing and problem solving)
00/01 ———————————————————-
Mechanics undergrad. level (Lecturing and problem solving)
Thermodynamics undergrad. level (Lecturing and problem solving)
Wave Physics and Modern Physics undergrad. level (Lecturing and problem solving)
Theoretical Surface Physics graduate level (Lecturing and problem solving)
01/02 ———————————————————-
Mechanics undergrad. level - “Mekanik del I på Elektrotekniklinjen Chalmers” (Lecturing and problem solving)
Thermodynamics undergrad. level - “Teachers program FYL220 Göteborgs Universitet”(Lecturing and problem solving)
Wave Physics and Modern Physics undergrad. level - “Naturvetenskapligt basår Göteborgs Universitet” (Lecturing and problem solving)
Modern Physics highschool level - “Tekniskt basår Chalmers Lindholmen” (Lecturing and problem solving)
Theoretical Surface Physics graduate level (Lecturing and problem solving)
02/03 ———————————————————-
Mechanics undergrad. level - “Mekanik del I på Elektrotekniklinjen Chalmers” (Lecturing and problem solving)
Thermodynamics undergrad. level - “Teachers program FYL220 Göteborgs Universitet”(Lecturing and problem solving)
Wave Physics and Modern Physics undergrad. level - “Naturvetenskapligt basår Göteborgs Universitet” (Lecturing and problem solving)
03/04 ———————————————————-
Mechanics undergrad. level - “Mekanik del I på E Chalmers” (Lecturing and problem solving)
Mechanics undergrad. level - “Mekanik del B på F Chalmers” (Problem solving)
Wave Physics and Modern Physics undergrad. level - “Naturvetenskapligt basår Göteborgs Universitet” (Lecturing and problem solving)
04/05 ———————————————————-
Mechanics undergrad. level - “Mekanik del I på E Chalmers” (Lecturing and problem solving)
Wave Physics and Modern Physics undergrad. level - “Naturvetenskapligt basår Göteborgs Universitet” (Lecturing and problem solving)
05/06 ———————————————————-
Wave Physics and Modern Physics undergrad. level - “Naturvetenskapligt basår Göteborgs Universitet” (Lecturing and problem solving)Wave Physics (LNA100) undergrad. level - “ Teachers program at GU” (Lecturing and problem solving)
06/07 ———————————————————-
Wave Physics (LNA100) undergrad. level - “ Teachers program at GU” (Lecturing and problem solving)07/08 ———————————————————-
Wave Physics (LNA100) undergrad. level - “ Teachers program at GU” (Lecturing and problem solving)08/09 ———————————————————-
Wave Physics (LNA100) undergrad. level - “ Teachers program at GU” (Lecturing and problem solving)13/14 ———————————————————-
Solid State Physica undergrad. level - “FFY011, Technical Physics program at Chalmers” (Problem solving)Mechanics undergrad. level - “Mechanics part A, Physics program at GU” (Lecturing and Problem solving)
Surface Physics master level course - “Chalmers” (Lecturing and Problem solving)
Physics for Engineers undergrad. level - “IT program at Chalmers” (Lecturing and problem solving)
14/15 ———————————————————-
Solid Mechanics undergrad. level - “LTK020, teachers program at GU” (Lecturing and Problem solving)Solid State Physica undergrad. level - “FFY011, Technical Physics program at Chalmers” (Problem solving)
Mechanics undergrad. level - “Mechanics part A, Physics program at GU” (Lecturing and Problem solving)
Mathematical Physics undergrad. level - “Mathematical Physica part A, Physics program at GU” (Lecturing and problem solving)
Physics for Engineers undergrad. level - “IT program at Chalmers” (Lecturing and problem solving)
15/16 ———————————————————-
Physics for Engineers undergrad. level - “IT program at Chalmers” (Lecturing and problem solving)
Mechanics undergrad. level - “Mechanics part A, Physics program at GU” (Problem solving)
Solid Mechanics undergrad. level - “LLTK90, teachers program at GU” (Problem solving)
Mathematical Physics undergrad. level - “Mathematical Physica part A, Physics program at GU” (Lecturing and problem solving)
16/17 ———————————————————-
Physics for Engineers undergrad. level - “IT program at Chalmers” (Lecturing and problem solving)
Solid Mechanics undergrad. level - “LLTK90, teachers program at GU” (Problem solving)
Mechanics undergrad. level - “Mechanics part A, Physics program at GU” (Problem solving)
Mathematical Physics undergrad. level - “Mathematical Physica part A, Physics program at GU” (Lecturing and problem solving)
17/18 ———————————————————-
Physics for Engineers undergrad. level - “IT program at Chalmers” (Lecturing and problem solving)
Mechanics undergrad. level - “Mechanics part A, Physics program at GU” (Problem solving)
Mathematical Physics undergrad. level - “Mathematical Physica part A, Physics program at GU” (Lecturing and problem solving)
18/19 ———————————————————-
Physics for Engineers undergrad. level - “IT program at Chalmers” (Lecturing and problem solving)
Mechanics undergrad. level - “Mechanics part A, Physics program at GU” (Problem solving)
Mathematical Physics undergrad. level - “Mathematical Physica part A, Physics program at GU” (Lecturing and problem solving)
19/20 ———————————————————- Physics for Engineers undergrad. level - “IT program at Chalmers” (Lecturing and problem solving) 20/21 ———————————————————- Physics for Engineers undergrad. level - “IT program at Chalmers” (Lecturing and problem solving) DISSERTATIONS I have been in the committee of the following dissertations and Licentiate thesis: - 1993 - August 1994 - 1998 - March 1999 - October 1998 - November 1999 - May 2000 - October 2000 - June 2002 - January 31 2003 - January 31 2003 - April 25 2003 - september 2003 - April 2 2004 - April 29 2004 SUPERVISION OF DIPLOMA WORKERS I have formulated and supervised three diploma works for undergraduate students. The diploma work is compulsory for the diploma of Master of Science in Engineering at Chalmers University of Technology. Aare Mällo -1984 worked with me on the problem of associative thermal desorption. We showed that a double peak structure in the thermal desorption spectra could be due to adsorbate-adsorbate interaction in contrast to the conventional interpretation of two adsorption sites. The work resulted in a publication [6]. Magnus Hurd -1987 studied a Langmuir-Hinshelwood type kinetic model for the catalytic reaction 2NO + 2H2 to N2 + 2H2O. He applied a computer program I developed for solving coupled rate equations (based on the multidimensional Newton Raphson method). The model was successful in reproducing the nitrogen production, when the initial sticking of NO and H2 were chosen to fit experimental results. It was concluded that water is formed by sequential addition of adsorbed atomic hydrogen. Johan Carlsson -1997 “Theoretical Investigation of the Structural and Electronic properties of ZnO”. The structure and the electronic properties of ZnO was analyzed. The investigation was performed by ab initio plane wave calculations with the program package Insight II from Biosym Inc. The plane wave program was based on the local density approximation and the pseudo potential approach to solid state calculations. Surface atom relaxation was calculated using a super cell including bulk, surface and vacuum. Good agreement with earlier calculations and experimental LEED data. Vasile Chis -2003 “First Principles Study of Surface Phonons of Metal Surfaces”. The phonon electron structure was studied applying the Density Functional Theory (DFT) based PWSCF code. Al(100) was investigated. Several localized phonon modes localized to the surface was found. Furthermore it was shown that the surface relaxation resulted in an outward displacement of the outermost surface layer. Due to the fact that the electron surface state penetrates deep into the bulk a slab of at least 20 layers has to be used in order to get a reasonable convergence with respect to phonon energies. Tomas Petersson -2004 “CO - Quantum Dot intercation - A Newns Anderson Study of Charge transfer”.Applying the Newns Anderson model ther Charge transfer was invetsigated as a CO molecule approach a free electron Quantum Dot (QD). With the anti-bonding 2pi* LUMO orbital of CO as the adsorption level it was shown that quantum effects was present for the charge transfer as the QD radius was small. Having a QD with an electron density of bulk sodium the charge transfere was oscillating as a function of QD radius with a maximum for a 6 electron QD. The behaviour is due to the fact that CO molecule with its axis normal to the cylidrically shaped QD surface will only couple to the azimuthal quantum number m=-1 and m=+1. Sriram Poyyapapakkam -2013 “First pronciples study of electronic and optical properties of biaxialy strained lanthanum nickelate” Strongly correlated metal oxide materials is an exotic class of compounds possible candidates for a number of applications especially in electronics and magnetic storage device applications. Some high Tc superconductors belongs to this category,a booming area of research today. Heterostructuring these oxide structures has led to realization of novel properties at the interfaces such as superconductivty and a two dimensional electron gas, not seen in the constitutent materials. One of the recently well studied metal-oxide structure is the LaNiO3/LaAlO3 superlattice. Lanthanum nickelate, LaNiO3 (LNO) is found to be in some extent analogous to cuprate superconductors and furthermore the only paramagnetic nickelate down to very low temparatures. The physics behind the properties of LNO is yet to be understood in detail in particular when it comes to lattice strain effects in ultra-thin LNO films. As a first step in an extended analysis of the electronic and optical properties of LNO, we perform first principle density functional theory (DFT) and linear response theory in the time dependent DFT formalism in order to find out about how much can be understood within a mean field description of the electron-electron interaction. Applying bilateral strain, changes in the low energy bandstructure was observed indicating charge transfer. This phenomena is referred to as self-doping, an interesting alternative to conventional chemical doping. SUPERVISION OF Licentiate students Johan Carlsson Jan 1997 – 4 June 1999 First-principles investigations of a metallic quantum well system - Na on Cu(111) Vanja Lindberg 2000-31 May 2002 Electron structure of adsorbed Quantum Dots Vasile Chis 2004-2006 Surface electron and phonon state phenomena Hugo Strand 2008 – 2011 Strong correlation - DMFT model study SUPERVISION OF PhD students Johan Carlsson 4 June 1999 – 15 March 2002 A first principles Study of Interface Systems: Electronic properties of Metal Quantum Wells and Varistor Materials Vanja Lindberg 31 May 2002 – 1 April 2005 Electron Structure and Reactivity of Adsorbed Metallic Quantum Dots Vasile Chis 2006 – 2009 First principles surface phonons and overlayer electronic structure Hugo Strand 2008 – 2013 Strong correlation - Models and Methods PEDAGOGICAL TRAINING The course “Supervising as a profession”, part I: 13-14 March 1995. held by J. Lindén, Lund University; part II: 9 Maj 1995, held by A. Mårtensson FU Chalmers University of Technology. DEPARTMENT WORK, CONFERENCES AND NETWORKS Interface Organized a seminar serie, “Interface”, every second Tuesday at the department during 1992-1993. The “Interface” meeting was a successful forum for short presentations in the field of physics and physical chemistry, which served as an interface between experimentalists and theorists. Pedagogical Support for PhD Students From the fall of 1999 to the fall of 2002 I was as a Pedagogical Support for PhD Students at the Department Physics and Engineering Physics at Chalmers University. My duty was to: - make sure that the new PhD student is introduced about (i) teaching and pedagogical courses, (ii) the role of the pedagogical support person and (iii) the pedagogical network among the PhD students. - support the students pedagogical development, (i) discuss the teaching profile of the student and (ii) available pedagogical courses. - be a general support for the student and to be a link between the student and the teacher responsible for the course in which the student take part as a teacher. - establish a document for the student on the received level of pedagogical competence at the end of the PhD period. 24 November 1999 I was invited by the Stenungssunds kommun to give a seminar: “New Age and Quantum Physics”. The seminar was followed by a vivid discussion. 27 November 1999, during the national wide Popular-Science-week , I organized an “Open house”, were members of our group presented ongoing experimental and theoretical work for the public. Head of Department of Physics, Gothenburg University, Januray 2009- June 2013 **Norfa Network Coordinator for the network “Quantum properties of nanostructures**“. **Norfa Workshop Organisor of the workshop “Quantum properties of nanostructures**“. LANGUAGE FACILITY ACCOMPLISHMENTS PRINCIPAL RESEARCH INTEREST Vibrational and translational damping of molecules on metal surfaces. Thermal desorption. Methods to calculate the density matrix in Quantum Statistical Mechanics. Modeling of surface reaction kinetics. Alkali metal promoted oxidation of semiconductors and semi-metals. Charge transfer processes in adsorbate-metal interaction Dissociation mechanism for oxygen on metals. Photostimulated processes at metal surfaces. ZnO Varistors-grain boundary physics. Quantum-well states in overlayers. first principles studies of alkali-overlayers on metals - Quantum-well states. Electron Dynamics of surface-localized electron states of metals. ZnO Varistors-grain boundary physics. Nano Catalysis; Electron Structure and Reactivity of adsorbed metallic Quantum Dots. Strong coupling in correlated materials. Electron-phonon coupling (EPC) in graphen and other 2D materials such as LiBC; lifetime broadening and EPC constant. SUMMARY OF RESEARCH PROGRESS During my time as a graduate student, in the group of prof. B.I. Lundqvist, I investigated the electron-hole pair mechanism for the damping of vibrational and translational motion of adsorbates on metal surfaces [1-5,7,8]. This study, based on a “first principle” Density Functional calculation scheme, showed that the electronic mechanism could be important for light adsorbates. The characteristic isotope- and temperature dependence of this contribution to the observed vibrational line width was pointed out in order to distinguish it from the contribution from the competing phonon mechanism. Molecular dynamics calculations have shown that the related electronic friction is reasonable, when considering hydrogen diffusion on metals (G. Wahnström 1991). The first direct measurement of vibrational lifetimes (CO/Pt(111)) using subpicosecond transient IR spectroscopy (R. Cavanagh 1991), gave lifetimes of the same order of magnitude as we predicted. From the additionally observed weak temperature dependence, it is concluded that the electron-hole pair mechanism is in operation. The diploma worker (examens arbetare) Aare Mällo worked with me on the problem of associative thermal desorption. We showed that a double peak structure in the thermal desorption spectra could be due to adsorbate-adsorbate interaction in contrast to the conventional interpretation of two adsorption sites. The work resulted in a paper [6]. As a Post.Doc. with prof. H. Metiu at the University of California in Santa Barbara, I developed methods for calculation of the density matrix [9-11]. The Fast Fourier Transform method (FFT), was found to be most efficient for the propagation of the density matrix in the imaginary time from the classical high temperature limit to an arbitrary low temperature. In the paper [11], I used FFT to solve the mixed real and imaginary time propagation, solving the Liouville’s equation to obtain the density matrix. In a model study, we applied this method to calculate the absorption line shape function considering a transition between two electronic states of a diatomic molecule in contact with a heat bath. During my stay in prof. B. Kasemos group I worked on two projects, (i) kinetic modeling of the catalytic water reaction on platinum [18,20,24,25], and (ii) alkali-metal-promotion of oxidation of graphite. In these projects I worked in close contact with experimentalists. In the first project, prof. A. Rosens group together with Kasemo made the measurements. We developed a kinetic model which could explain the observed temperature and H2/O2 mixture dependence of the hydroxyl and water production for intermediate total pressures (1-100 mtorr). With use of the kinetic model, we were able to extrapolate to higher pressures, where we predicted hydrogen poisoning of the surface. In the second project, I worked primarily together with Peter Sjövall, who performed the experiments. The model I proposed could qualitatively and semi quantitatively explain the enormous increase of the oxidation rate of graphite, when small amounts of alkali atoms were preadsorbed. The model was based on the idea that as the alkali will cause an up-shift of the Fermi level (decrease of work function), there will be an increase of the charge transfer from the surface to an antibonding molecular orbital of the oxygen molecule, which will stimulate dissociation. The oxygen atoms will further easily react with the carbon atoms of the graphite surface. During this period of time I visited prof. V.P. Zhdanov at the Institute of Catalysis in Novosibirsk, USSR. Ever since, we have collaborated on different projects The past year I have performed studies of the interaction between the oxygen molecule and metal surfaces [26,31]. In collaboration with S. Gao, I have used an embedding cluster scheme (S. Gao 1991) to study the electron structure of chemisorbed molecular oxygen on the metals. We observed strong shifts and broadenings of the chemically active molecular levels of oxygen and in connection with this, a significant donation of electron charge to the molecule from the surface. The results presented in [26,31] indicate that the qualitative difference, when the molecule interacts with a noble- or transition metal surface, is attributed to the different location of the d-band on the energy scale. The results are in qualitative agreement with experiments. In collaboration with Zhdanov, I have studied non-adiabatic effects in atom-metal surface scattering. These effects appear due to a finite velocity of the atom approaching the surface. We also investigated the effects of the intra-atomic coulomb repulsion on the charge transfer between the atom and the molecule. In agreement with experimental observations for Na scattering on a copper surface, at incoming kinetic energies of 10-100 eV, we have found that the intra-atomic coulomb repulsion will give rise to a relatively large probability of creating positive ions [27]. We hope to further develop this scheme of calculation to study possible non-adiabatic effects for the dissociation of diatomics, such as the oxygen molecule. By the beginning of 1992 I started to work in the field of surface photochemistry. I have investigated the direct mechanism for photoinduced desorption and dissociation of O2 on Pt(111) [28]. Information about the local density of states is obtained from an embedded cluster calculation scheme, the same as used in previous studies [26,31]. From an experimental point of view, different aspects of the cross section has been studied, by varying (i) photon frequency, (ii) polarization of the light, p- and s-polarized, and (iii) angle of incidence of the light. I found reasonable agreements with experiments considering, (i) the onset for the desorption and dissociation yields as a function of foton frequency and (ii) the angular dependencies of the cross sections for unpolarized light. However, polarized light experiments on the similar system O2/Pd(111) showed qualitatively different angular dependencies compared to the calculated ones. Furthermore, taking quenching into account, the calculated cross sections are 2-3 orders of magnitude less than experimentally measured. My conclusion was that the indirect, “hot electron”, mechanism probably dominates in the process. This conclusion was also supported by the experimental observation that the cross section for desorption and dissociation have similar angular dependence on the angle of incident light as the substrate absorbance. Photoinduced desorption and dissociation of O2 on metals. A theoretical model is developed in order to investigate the hot electron mechanism in photoinduced surface reactions. We applied the model to discuss the experimentally measured photoinduced desorption and dissociation of O2 on Pd(111) and Ag(110). The photo energy dependence of the cross section is in reasonable agreement with experiment [29,30]. In a separate paper we have analyzed the survival probability and in particular tried to explain why, according to experiments, this probablity seems to be larger than expected. For photoinduced dissociation of chemisorbed molecules, locking of vibrational excitations due to Franck-Condon factors, could take place in the electronically excited state. This will lead to an effective electron capture width which is relatively small [33]. O2 dissociation on metals. In collaboration with prof. P. Nordlander and L. Lou, I am further investigating the chemisorption system O2 on metals. In the previous study [26,31], in collaboration with S. Gao, of chemisorbed O2 on Cu(100), Ni(100) and Pt(111), using a semi-empirical embedding scheme resulted in qualitatively different results in comparison with other investigations. The main difference was that we found the d-states of the transition metals to be most important, considering interaction and charge transfer. This is in clear contrast to quantum chemistry calculations. We have been studying the system O2 on copper and nickel clusters using first principles methods based on the Density Functional scheme with LDA. The total energies are calculated and in particular the restricted minimum energy path of the molecule is determined. The character of the molecule-cluster bond is investigated and a detailed mapping of the change of the bond structure which lead to dissociation as the molecule approach the cluster. Our first comparative study of molecular oxygen approaching a relatively small nickel and copper cluster is presented in the publication [34]. Photoinduced desorption of potassium atoms from graphite. Photoinduced desorption of K from a graphite surface is investigate experimentally in Prof. B. Kasemos group working in our department. Detailed information is obtained, such as photoinduced desorption yield dependence on K-coverage, photon energy and polarization of the light. The results indicate that an indirect “hot electron” mechanism is in operation. In collaboration with the experimental group and Prof. V.P. Zhdanov several papers have been accepted for publication [28, 29, 30, 32, 33, 35, 36, 37]. Electron structure of K/Graphite. First principles electron structure calculations of the system potassium on graphite. This is a collaboration with L. Lou, Wavefunction Irvine, California and presently with L. Österlund, Competence Centre for Catalysis at Chalmers. This mainly theoretical investigation is stimulated by our earlier results from the photo experiment [32,35,36,37]. Important issues that we have focused on are, (i) potassium induced electron structure, (ii) the degree of charge transfer from potassium to the graphite surface as a function of potassium coverage, (iii) barriers for potassium diffusion along the graphite surface and into the bulk of graphite (intercalation) and (iv) structural phase transition. Recent resluts are reported in the publications [39,42]. PRESENT AND FUTURE PROJECTS Experimental and theoretical investigation of the ZnO grain boundaries Electronic Structure and Reactivity of Quantum Dots My PhD student Vanja Lindberg has performed a model study of a cylindrical quantum dot (QD) [43,49] and is now working with collaborators in professor Risto Nieminens group in Helsinfors. We are performing first principle DFT calculation of a cylindrical quantum dot applying the MIKA real-space code [55]. One of the more important issues is to investigate how an adsorbed molecule on the QD will be influenced by the size of the dot. In particular, the dot-size-dependence of activation barrier and chemical bonding is of interest. Hole lifetime of quantum well states in alkali overlayers on metals. Lifetime of surface states and image states on metals - including electron-phonon and electron-electron interaction. A collaboration with the San Sebastian group; professor P.M. Echenique, professor E. Chulkov and PhD student A.E. Goienetxea. The aim is to compare the contributions from electron-phonon and electron-electron interaction to the experimentally observed lifetimes of surface states and surface image states on clean metal surfaces. We have investigated the surface state of Cu(111) and Ag(111) and compared with High Resolution PES data [47,50,53] Strong correlation in electron systems (2008-). DMFT studies of the phase diagram of Mott insulator. LDA+U and LDA+Gutzwiller invetsigations of bulk STO and LAO and the 2D electron gas in the interface of LAO/STO. Electron-phonon coupling in graphene. LIST OF PUBLICATIONS Electronic damping of adsorbate vibrations on metal surfaces. Theoretical studies of molecular adsorption on metal surfaces. Electronic damping mechanism for vibrations, rotations and translations of adsorbates on metal surfaces. Electronic damping of motions of adsorbates on metal surfaces. Electronic damping of atomic and molecular vibrations at metal surfaces. A simple model for thermal associative desorption. Electron-hole pair damping of the motion of adsorbates: Charge transfer and potential scattering. Electronic mechanism for desorption. Two simple methods for computation of the density matrix of “heavy” quantum particles. A fast Fourier transform method for calculating the equilibrium density matrix. An efficient method for solving the Quantum Liouville Equation: Application to the electron absorption spectroscopy. Static and dynamic properties of a dipole on a metal. A finite cluster approach to the electron-hole pair damping of the adsorbate vibrations: CO adsorbed on Cu(100). Field adsorption and desorption of hydrogen on W(100); and atom-probe study. Potassium promotion of carbon reactivity - 10000-fold increase in the oxidation rate. Kinetic model and experimental results for the H2O and OH production rates on Pt. The island model of a Langmuir-Hinshelwood reaction. Kinetic model study of the OH and H2O production on Pt. Influence of potassium on the oxidation rate of carbon. Determination of the activation energy for OH desorption in the H2 + O2 reaction on polycrystalline platinum. Electronic mechanism for the alkali-metal-promoted oxidation of semiconductors. Electronic mechanism for the alkali-metal-promoted dissociation of oxygen on semiconductors. Effect of surface reconstruction on the apparent Arrhenius parameters for desorption. Hydroxyl desorption from platinum in the catalytic formation reaction and decomposition of water. Kinetics of the hydrogen-oxygen reaction on platinum. Molecular oxygen on metals. Effect of intra atomic coulomb repulsion on charge transfer in atom metal surface scattering. Direct mechanism for photoinduced desorption and dissociation of O2 on Pt(111). Theory of photostimulated desorption and dissociation of Substrate-mediated mechanism for photoinduced chemical reactions on metal surfaces Molecular chemisorption of oxygen on Cu(100), Ni(100) and Pt(111). Photoinduced desorption of metal adsorbates: potassium on graphite. Photoinduced substrate mediated dissociation of O2 on Pd(111); evaluation of the survival probability. Theoretical study of O2 on copper and nickel clusters. Photoinduced desorption of potassium atoms on graphite. Photon induced desorption and intercalation of potassium atoms deposited on Graphite(0001). Photoinduced desorption of potassium atoms from a two-dimensional overlayer on graphite. High- Resolution Photoemission from Tunable Quantum Well: Cu(111)/Na. Potassium on graphite - Electron structure and Photodesorption Phonon-induced damping of a quantum well hole state: 1 ML Na on Cu(111). A first principles investigation of the quantum well system - Na on Cu(111). Electronic Structure and Kinetics of K on Graphite. Quantum Dots - a simple free electron model. The Electronic Properties of a Grain Boundary in Sb-Doped ZnO . Electronic Structure of a Bi-doped Sigma=13 tilt grain boundary in ZnO. Segregation Effects at a High-Angle Twist Boundary in ZnO Role of bulk and surface phonons in the decay of metal surface states Theoretical invetsigation of pure and Zn-doped alpha- and delta-phase of Bi2O3 Model study of Quantum Dots. Model study of Quantum Dots. Image state phonon scattering resolved in energy and momentum Electron-Phonon coupling at Metal Surfaces Charge accumulation and barrier formation at grain boundaries in ZnO decorated with Bi Model study of adsorbed metallic quantum dots: Na on Cu(111) Phonon-mediated decay of metal surface states Applications of quantum mechanics and many-body theory to resolve electron dynamics Phonon mediated image state electron decay at metal surfaces Lifetime of holes and electrons at metal surfaces; electron-phonon coupling Charge transfer and re-bonding effects at doped alpha and delta-phases of Bi2O3 Effect of doping a grain boundary in ZnO with various concentrations of Bi. Hole dynamics in a quantum-well state at Na/Cu(111) An interfacial complex in ZnO and its influence on charge transport The formation of defect complexes in a ZnO grain boundary Surface relaxation influenced by surface states Metallic quantum dots Electron-phonon coupling and lifetimes of excited surface states Quantum size effects of CO reactivity on metallic quantum dots Overlayer resonance and quantum well state of Cs/Cu(111) studied with angel-resolved photoemission, LEED and first principles calculations *Evidence of longitudinal resonance and optical sub-surface phonons in Al(100)* Two dimensional localization of fast electrons in p(2x2)-Cs/Cu(111)Phys. Rev. B (in press) V. Chis, S. Caravati, G. Butti, M.I. Trioni, P. Cabrera-Sanfelix, A. Arnau and B. Hellsing Large surface charge-density ocsillations induced by second-layer surface phonon resonances,Phys. Rev. Lett. 101,206102(2008), V. Chis, B. Hellsing, G. Benedek, M. Bernasconi, E. Chulkov and J.P. Toennies Model calculation of the electron-phonon coupling in Cs/Cu(111) [](http://fy.chalmers.se/%7Ehellsing/publications/PhysRevB_78_035417_2008.pdf) Phys. Rev. B 78(2008)035417 A. Nojima, K. Yamashita and B. Hellsing Sodium and potassium monolayers on Be(0001) investigated by photoemission and electron structure calculation,Phys Rev B 78(2008)085102, J. Algdal, T. Balasubramanian, V. Chis, B. Hellsing, S.-Å.Lindgren and L. Wallden Model Eliashberg function for surface states Applied Surface Science, 254(2008)7938, A. Nojima, K. Yamashita and B. Hellsing Calculational aspects of electron-phonon coupling at surfaces, Phys: Condens. Matter, 20(2008)224018, A. Nojima, K. Yamashita and B. Hellsing Photoelectron driven acoustic surface plasmon , Phys. Rev. B, Brief Report (in press) V.M. Silkin, B. Hellsing L. Wallden, P.M. Echenique, E.V. Chulkov Theory of Surface Phonons at Metal Surfaces: Recent Advances, J. Phys. Condens. Matter 22(2010)0844020, G. Benedek, M. Bernasconi, V. Chis, E. Chulkov, P.M. Echeniques, B. Hellsing and J.P. Toennies A detailed derivation of Gaussian orbital-based matrix elements in electron structure calculations, Eur. J. Phys. 31(2010)37, T. Petersson, B. Hellsing Theory of Surface Phonons at Metal Surfaces: Recent Advances, J. Phys. Condens. Matter 22(2010)0844020, G. Benedek, M. Bernasconi, V. Chis, E. Chulkov, P.M. Echeniques, B. Hellsing and J.P. Toennies Photoelectron driven acoustic surface plasmon, Phys. Rev. B, Brief Report 81(2010)113406 V.M. Silkin, B. Hellsing L. Wallden, P.M. Echenique, E.V. Chulkov Time-dependent mean field theory for dynamics in quantum dots, arXiv:1102.2741,(cond-mat.mes-hall), N. Lanata, H. Strand The Dynamical Mean Field Theory phase space extension and critical properties of the finite temperature Mott transition , Phys. Rev. B, 83(2011)205136, H. Strand, A. Sabashvili, M. Granath, B. Hellsing, S. Ostlund. Efficient implementation of the Gutzwiller variational method , Phys. Rev. B, 85(2012)035133, N. Lanata, H. Strand, X. Dai, B. Hellsing. Oxygen vibrations and acoustic surface plasmon on Be(0001), Phys. Rev. B, 86(2012)085453, M. Jahn, M. Muller, M. Endlich, N. Neel, J. Kröger, V. Chis, B. Hellsing. Orbital Selectivity in Hund’s metals: The Iron Chalcogenides, Phys. Rev. B 87, 045122 (2013), N. Lanatà, H. U. R. Strand, G. Giovannetti, B. Hellsing, L. de’ Medici, M. Capone Plasmaron excitations in p(2×2)-K/Graphite, Phys. Rev. B (in press), arXiv:submit/0930372 [cond-matrl-sci] 11 Mars 2014, V. Chis, V.M. Silkin, B. Hellsing For later publications see "Publications" Invited talks Invited talk at the symposium “Hundred years of the Arrhenius law” in The title of my talk was: “Theory of Chemical Reactions on Surfaces”. Jerusalem, Israel, In May 1992. Plenary lecture “Quantum Phenomena in Surface Physics” at the conference “Foundations of Probability and Physics - 2”. Växjö, Sweden, June 2-7 2002. Invited talk:“Phonon induced Electron Dynamics on Metals” Invited talk:“Electron-phonon coupling at metal surfaces” at the Werner Brandt Workshop. Invited talk:“Application of Quantum Mechanics and Many-Body Theory to Resolve Solid State Experiments on Electron Dynamics” at the conference “Reconsideration of Foundations - 2”. Invited talk:“Nano Catalysis and Lifetimes of Exited States at Metal Surfaces” at the conference (IWNMS-2004) “Nano Materials, Magnetic Ions \& Magnetic Semiconductors Studied Mostly by Hyperfine Interactions “. Invited talk:“Lifetime calculations of excited surface states” at the summer school “EPIOPTICS-8” . Invited talk: Lifetimes of surface state excitations on metals - contributions from electron-phonon coupling. Invited talk: Electron-phonon coupling and lifetimes of excited surface states”. Invited talk: “Anomalous surface phonon resonances of Cu(111) and electronresonances of Cs p(2X2) on Cu(111)”. Conference: International workshop on quantum dynamics and quantum simulations,Institute of Physics, Beijing, China, May 2006 Invited talk:Surface phonons and lifetimes”, Invited talk: “Surface electron-phonon coupling”, Invited talk: “Surface electron-phonon interaction”, Invited talk: “Anomalous elecron and phonon dynamics”, Invited talk: “Correlated multiorbital systems, a Gutzwiller study”, Invited talk: “Plasmaron excitations in p(2×2)-K/Graphite”, Invited talk:“Lifetime calculations of excited surface states” at the summer school “EPIOPTICS-13 and Silicene-1” . Invited talk:“Plasmaron footprints in photoemission” at the conference “SPP2015” . Invited talk:“Strong electron-phonon coupling in graphene” at Computational Sceince Research Center (CSRC), Beijing in China, December 2015 CONFERENCE PRESENTATIONS (contributing talks and posters) “Influence of admolecule-metal charge fluctuation on the vibrational life time of the molecule.” “The electronic dissipation mechanism for adsorbates on metal surfaces.” “Electronic damping mechanism for vibrations, rotations and translations of adsorbates on metal surfaces.” “Electronic damping of vibrational motion on metal surfaces.” “Vibrational damping and friction for hydrogen on metal surfaces” “Electron-hole pair damping of the motion of adsorbates; Charge transfer and Potential scattering.” “K-promoted CO production on Graphite.” “Kinetic model and experimental results for H2O and OH production rates on Pt.” “Investigation of the catalytic water reaction on Pt; kinetic modeling in comparison with measurements of OH-desorption.” “Electronic mechanism for alkali-metal-promoted dissociation of “Kinetics of the hydrogen-oxygen reaction on platinum.” “Kinetics of the catalytic water formation reaction on platinum.” “O2/Cu(100) and O2/Ni(100)” “Chemisorbed Molecular O2 on metals.” “Influence of intra-atomic Coulomb interaction on charge transfer “Photoinduced dissociation of O2 on Pt(111)” “Theoretical investigation of photoinduced desorption and “Mechanism for photoinduced reactions at metal surfaces” “Theory of photodesorption - K/Graphite” “Theory of photodesorption - K/Graphite” “Photoinduced desorption of potassium atoms on graphite.” “Photoinduced desorption of K atoms from graphite - cross section, velocity distribution and hot electrons.” “Hole dynamics in Na monolayer on Cu(111)” “Potassium adsorption on graphite - first principles Electron structure study” “Hole Lifetime of Quantum-well States” “Potassium adsorption on graphite - Electron structure and Photodesorption” “Phonon-induced decay of a quantum-well hole: 1 ML on Cu(111)” “Na on Cu(111); Electron structure and Dynamics” “Phonon-induced decay of a quantum-well hole: 1 ML on Cu(111)” “Role of bulk and surface phonons in the decay of metal surface states” “Electron-Phonon coupling at metal surfaces” “Electron and phonon structure of Cs/Cu(111), “Surface Phonons and electrons” “Two dimensional fast electrons at surfaces”, “PHOTOELECTRON DRIVEN PLASMARON EXCITATION IN (2X2)K/GRAPHITE”, “Plasmaron footprints in photoemission”, INVITED VISITS In July 1987 I was invited to the Institute of Catalysis, Novosibirsk, USSR for three weeks. During this period I collaborated with prof. Zhdanov. I gave two seminars: “Alkali promoted oxidation of graphite” “Catalytic water and hydroxyl production on platinum” In January 1989 I gave three invited talks in USA with the title “Electronic mechanism for alkali-metal-promoted oxidation of semiconductors” at the locations: IBM T.J. Watson Research Center, Yorktown Heights. Department of Physics and Astronomy, Rutgers University. Laboratory of Atomic and Solid State Physics and Material Science Center, Cornell University. The last two month of 1992 I was invited as a visiting lecturer to the Physics Department of Rice University in Houston, Texas, USA. I collaborated with prof. P. Nordlander and his group and gave three seminars at Rice University: “Electron structure of molecular oxygen chemisorbed on metals” “Photoinduced processes at metal surfaces; Desorption and Dissociation of O2 on Pt(111)” During my stay in USA I also gave the talk “Photoinduced processes at metal surfaces; Desorption and Dissociation of O2 on Pt(111)” in two groups at two other locations: Prof. White at Department of Chemistry and Biochemistry, University of Texas, Austin, USA. Prof. Polyani at Department of Chemistry, University of Toronto, Toronto, Ontario, Canada. 24 November 1999 I was invited by the Stenungssunds kommun to give a seminar: “New Age and Quantum Physics”. The seminar was followed by a vivid discussion. In November 1999 I was invited to the The University of the Basque Country, San Sebastian in SPAIN to take part in a dissertation committee and to give a seminar “Phonon-induced decay of a quantum-well hole; 1 ML of Na on Cu(111).” During year 2000 I was invited by Professor Pedro Miguel Echenique as a visiting professor for 3 month at Donostia International Physics Center (DIPC), San Sebastian in Spain. I spent July, August and September at DIPC. In November 2000 I was invited by Professor Risto Nieminen to give the seminar “Lifetimes of surface localized states of metals” at the Laboratory of Physics at the Helsinki University of Technology in Finland. On the 8 december 2000 I was invited by the Växjö University to give a lecture “Quantum-size effects on solid state surfaces”. During year 2001 I was invited by Professor Pedro Miguel Echenique as a visiting professor for 2 month at Donostia International Physics Center (DIPC), San Sebastian in Spain. I spent June and July at DIPC. During year 2003 I was invited by Professor Pedro Miguel Echenique as a visiting professor for 1 month at Donostia International Physics Center (DIPC), San Sebastian in Spain. I spent the month of July at DIPC. Mars 2004 I was invited to University of Milan in Italy by Prof. Giorgio Benedek. Seminar: “Nano Cataylsis and Lifetimes of Surface states”. During the month of July 2006 I was invited by Professor Pedro Miguel Echenique as a visiting professor at Donostia International Physics Center (DIPC), San Sebastian in Spain. July 2012 I was invited by Professor Pedro Miguel Echenique as a visiting professor for one month at Donostia International Physics Center (DIPC), San Sebastian in Spain. I gave one seminar July 17 2012;Correlated multiorbital systems, a Gutzwiller study August and September 2013 I was invited by Professor Pedro Miguel Echenique as a visiting professor at Donostia International Physics Center (DIPC), San Sebastian in Spain. I gave one seminar ;DFT study of strain effects in lanthanum nickelate 13-20 December 2015 I was invited by Prfessor Shiwu Gao as a visiting professor at Computational Sceince Research Center (CSRC), Beijing in China.
PhD Thesis - “Calculations of Linear and Nonlinear Optical Properties of Ionic Crystal Surfaces and Fullerenes”
by Erik Westin,
Department of Physics, Chalmers University of Technology, Göteborg.
PhD Thesis - “Catalytic Reactions Studied with Metal-Oxide-Semiconductor Structures”
by Joakim Fogelberg,
Department of Physics, Linköping University, Linköping.
PhD Thesis - “Model studies of water and small biomolecules at solid surfaces”
by Patrik Löfgren,
Department of Applied Physics, Chalmers University of Technology, Göteborg
PhD Thesis - “Efficient density-functional-based calculational methods for surfaces”
by Lennart Bengtsson,
Department of Applied Physics, Chalmers University of Technology, Göteborg
Licentiate Thesis - “Bulk and Surface Structure of Kappa-Alumina”
by Carlo Ruberto,
Department of Applied Physics, Chalmers University of Technology, Göteborg
PhD Thesis - “Dynamic effects in the interaction of charged particles with solids:
energy losses in insulators and low energy electron lifetimes”
by Enrique Zarate Larrinaga,
The University of the Basque Country, San Sebastian, SPAIN
Licentiate Thesis - “Diffusion, Nucleation, and Island Growth in Metal-on-Metal Epitaxy”
by Staffan Ovesson,
Department of Applied Physics, Chalmers University of Technology, Göteborg.
Licentiate Thesis - “First-Princilpes Density-Functional Computational Experiments to Understand the Nature of Metal-Carbonitride Interface Adhesion”
by Sergey Dudiy,
Department of Applied Physics, Chalmers University of Technology, Göteborg.
Licentiate Thesis - “Experimental and theoretical investigation of two surface alloys: Al(100)-Na and Al(100)-Li”
by Mikael Borg,
Naturvetenskapliga fakulteten, Lunds Universitet, Lund.
Licentiate Thesis - “Aspects of the catalytic water production from first-principles calculations”
by Gustav Karlberg,
Department of Applied Physics, Chalmers University of Technology, Göteborg.
PhD Thesis - “Tuning the electrical and optical properties in low-dimensional structures”
by Per Sundqvist,
Physics and egineering of physics, Chalmers, Göteborg.
PhD Thesis - “From Oxygen to Oxide: First-Principles Study of Some Key Aspects”
by Behrooz Razaznejad,
Department of Applied Physics, Chalmers University of Technology, Göteborg.
PhD Thesis - “Electron-phonon interactions on metal surfaces”
by Asier Eiguren,
Department of Material Physics, University of San Sebastian, San Sebastian, Spain.
PhD Thesis - “Laser diagnostics and kinetic modelling of the reaction intermediates in catalytic combustion”
by Åsa Johansson,
Department of Physical Chemistry, Göteborg University, Göteborg.
PhD Thesis - “Electronic states of Adsorbates and Insulating Overlayers on Metal Surfaces”
by Fredrik Olsson,
Department of Applied Physics, Chalmers University of Technology, Göteborg.
Financing from NorFa (2004-2006) 300.000 Nok/year
at Hjortviken 1-4 June 2004.
**
PROFESSIONAL ORGANIZATION**
American Physical Society.
English: general fluency, French: some skill.
91 publications in international scientific journals.
40 presentations international conferences (25 oral and 15 posters),
( 9 of the oral presentations were invited talks).
18 invited seminars and visits.
1980-1984
1985-1986
1986-1989
1989-1993
1993-
1996-
(indicated references are found in the “LIST OF PUBLICATIONS”)
The computer program I developed for solving the coupled rate equations (based on the multidimensional Newton Raphson method) can more or less be used as a “black box” for an arbitrary reaction. This program has been used by the A. Rosens group to model the “back” decomposition reaction of water. It was also used by a diploma worker of mine, Magnus Hurd, to study the catalytic reaction 2NO + 2H2 to N2 + 2H2O reaction.
The basic ideas of this project lead me to further developed the model to study the observed alkali promoted oxidation of semiconductor surfaces [21,22].
.
Me and Eva Olsson at the Department of Physics at Chalmers University of Technology propose a project devoted to a study of the basic physics underlying the operation of the ZnO varistor (see a separate NFR application). The project is based on a unique collaboration between experiment-theory-industry. The clear and applied aims raised by the industry ABB Switchgear AB in Lundvika is to find the key parameters responsible for the non-linear IV characteristics, in order to optimize the varistor function.
We will investigate the influences on the IV characteristics, referring to (i) crystal surface orientations at the grain boundary and (ii) inter facial impurities. This basic experimental and theoretical research regarding the grain boundaries is also of interest in a broader sense, e.g. for the understanding of high temperature super conductors.
Since January 1997 I have a student working on electron structure calculations on ZnO. He has produced a Diploma Thesis (supervised by me) “Theoretical Investigation of the Structural and Electronic properties of ZnO”.
During a two month stay, August and September year 2000 at the University of Cambridge Johan has started up a collaboration with the group of Paul Bristow, head of the department of Material Science and Metallurgy. We shear a common interest to perform first principles studies of ZnO grain boundaries (GB). This collaboration has been very fruitful end covers studies of GB doping by Sb and Bi doping as well as incorporating Zn vacancies and O interstitials [44,45,46,48,51,52,54]. Bi doping at reasonable concentrations form donor states in the ZnO bandgap and the complex including Bi doping, Zn vacancies and O interstials form acceptor states. In the latter case the Double Shottky Barrier model applies and the ZnO non-linear characteristics could be explained
This project is in collaboration with experimental work by professor L. Walldén and S.Å. Lindgren and A. Carlsson at our department. From a self-energy analysis of a quantum well hole state in an alkali overlayer on Cu(100), an expression for the electron-phonon induced lifetime broadening is derived. The electron wave function of quantum well states in the overlayer are quantized normal to the surface and of plane-wave type parallel to the surface. According to our model, the temperature dependent part of the contribution to the width of the observed Lorentzian shaped photo-emission line originates from phonon mediated electron scattering from inter-sub band scattering from nearby resonance states. This imply that the electrons couples predominantly to phonon modes polarized perpendicular to the surface, the so called organ-pipe like modes. Comparing the theoretically predicted temperature dependent lifetime broadening with experiment give information of the strength of the electron-phonon coupling strength in metal overlayers, the T-independent part of the broadening and the complex interplay of phonon energies, temperature and hole-state energy. Publications [38,40,41].
We are planning to set up a calculation of the system Cs/Cu(111) as this system has been characterized experimentally by Wallden et al. in details both concerning the formation of quantum well states (QWS), vibrational properites and low temperature ARPES measurements are in progress giving information about the lifetime broadening. We will obtain the electronic and vibrational structure which will serve as an input to the investigation of the fundamental electron-phonon and electron-electron scattering responsible for the lifetime broadening. Collaboration with the local experimental group and the San Sebastian group.
M. Persson and B. Hellsing,
Phys. Rev. Lett.9 (1982) 662.
B.I. Lundqvist, B. Hellsing, S. Holmström, P. Nordlander, and
M. Perssson,
International Journal of Quantum Chemistry XXIII (1983) 1083.
B. Hellsing, M. Persson, and B.I. Lundqvist,
Surface Sci. 126 (1983) 147.
M. Persson, B. Hellsing, and B.I. Lundqvist,
J. Electr. Spectr. Rel. Phen. 29 (1983) 119.
B. Hellsing and M. Persson,
Physica Scripta 29 (1984) 360.
B. Hellsing and Aare Mällo,
Surface Sci. 144 (1984) 336.
B. Hellsing,
Surface Sci. 152⁄153 (1985) 826.
B. Hellsing,
J. Chem. Phys. 83 (1985) 1371.
B. Hellsing, S. Sawada, and H. Metiu,
Chem. Phys. Lett. 122 (1985) 303.
B. Hellsing, A. Nitzan, and H. Metiu,
Chem. Phys. Lett. 123 (1986) 523.
B. Hellsing, A. Nitzan, and H. Metiu,
Chem. Phys. Lett. 123 (1986) 523.
S. Holmström and B. Hellsing,
Surface Sci. 166 (1986) 249.
T.T. Rantala, A. Rosen, and B. Hellsing,
J. Electr. Spectr. Rel. Phen. 39 (1986) 173.
M. Hellsing and B. Hellsing,
Surface Sci. 176 (1986) 249.
P. Sjövall, B. Hellsing, K.E. Kech, and B. Kasemo,
J. Vac. Sci. Technol. A5 (1987) 1065.
B. Hellsing, B. Kasemo, S. Ljunström, A. Rosen , and T. Wahnström,
Surface Sci. 189⁄190 (1987) 851.
B. Hellsing and V.P. Zhdanov,
Chem. Phys. Lett. 147 (1988) 613.
B. Hellsing and B. Kasemo,
Chem. Phys. Lett. 148 (1988) 465.
P. Sjövall, B. Hellsing, K.E. Kech, and B. Kasemo,
Mat. Res. Soc. Proc. 111 (1988) 447.
T. Wahnström, E. Fridell, S. Ljunström, B. Hellsing, B. Kasemo, and A. Rosen,
Surface Sci. Lett. 223 (1989) 1905.
B. Hellsing,
Phys. Rev. B 40 (1989) 3855.
B. Hellsing,
Vacuum 41(1990)628.
B. Hellsing and V.P. Zhdanov,
Chem. Phys. Lett. 6 (1990) 584.
E. Fridell, B. Hellsing, B. Kasemo, S. Ljungström, A. Rosen, and T. Wahnström,
J. Vac. Sci. Technol. A9 (1991) 2322.
B. Hellsing, B. Kasemo, and V.P. Zhdanov,
J. Catal. 132 (1991) 210.
B. Hellsing and S. Gao,
Chem. Phys. Lett. 187 (1991) 137.
B. Hellsing and V.P. Zhdanov,
Surface Sci. 274 (1992) 411.
B. Hellsing,
Surface Sci. 282 (1993) 216.
molecular oxygen on metals.
B. Hellsing and V.P. Zhdanov,
J. Electr. Spectr. Rel. Phen. 64⁄65 (1993) 563.
B. Hellsing and V.P. Zhdanov,
J. Photochem. Photobiol. 79 (1994) 221.
B. Hellsing and S. Gao,
Solid State Commun. 90 (1994) 223.
D.V. Chakarov, L. Österlund, B. Hellsing, V.P. Zhdanov and B. Kasemo,
Surface Sci. Lett. 311 (1994) L724.
B. Hellsing and V.P. Zhdanov,
Chem. Phys. Lett. 226 (1994) 331.
L. Lou, P. Nordlander and B. Hellsing,
Surface Sci. 320 (1994) 320.
B. Hellsing, D.V. Chakarov, L. Österlund, V.P. Zhdanov and B. Kasemo,
Surface Sci. 363 (1996) 247.
D.V. Chakarov, L. Österlund, B. Hellsing and B. Kasemo,
Appl. Surface Sci. 106 (1996) 186.
B. Hellsing, D.V. Chakarov, L. Österlund, V.P. Zhdanov and B. Kasemo,
J. Chem. Phys. 106 (1997) 982.
A. Carlsson, B. Hellsing, S.-Å. Lindgren and L. Walldén,
Phys. Rev. B 56 (1997) 1593.
B. Hellsing,
Proc. of the VIII Inter. Workshop on Ion Beam Surface Diagn. 1 (1998) 79.
B. Hellsing , J. Carlsson, S.-Å. Lindgren and L. Walldén,
Phys. Rev. B 61 (2000) 2343.
J. Carlsson and B. Hellsing
Phys. Rev. B 61 (2000) 13973.
L. Lou, L. Österlund and B. Hellsing,
J. Chem. Phys. 112 (2000) 4788.
V. Lindberg and B. Hellsing,
Phys. Rep. Series-2001, Växjö University.
J. Carlsson, B. Hellsing, H.S. Domingos and P.D. Bristowe,
J. Phys. Condens. Matter 13 (2001) 9937.
J. Carlsson, H.S. Domingos, B. Hellsing and P.D. Bristowe,
Interface Sci. 9 (2001) 143.
H.S. Domingos, J. Carlsson, P.D. Bristowe and B. Hellsing
Interface Sci. 9 (2001) 231.
A. Eiguren, B. Hellsing, F. Reinert, G. Nicolay, E. V. Chulkov, V. M. Silkin, S. Hufner and P. M. Echenique
Phys. Rev. Lett. 88 (2002) 066805-1.
J. Carlsson, B. Hellsing, H.S. Domingos and P.D. Bristowe
Phys. Rev. B 65 (2002) 205122.
V. Lindberg and B. Hellsing
Surface Science 506 (2002) 297.
V. Lindberg and B. Hellsing
Surface Science 506 (2002) 297.
A. Eiguren, B. Hellsing, E. Chulkov and P. Echeinque
7th International Conference on Nanometer-Scale Science and Technology and 21st European Conference on Surface Science(2002) 2
B. Hellsing, A. Eiguren and E. V. Chulkov
J. Phys.: Condens. Matter 14 (2002) 5959.
H.S. Domingos, P.D. Bristowe, J. Carlsson and B. Hellsing
J. Phys.: Cond. Matt. 14 (2002) 12717.
T. Torsti, V. Lindberg, M.J. Puska and B. Hellsing
Phys. Rev. B 66 (2002) 235420.
A. Eiguren, B. Hellsing, E. V. Chulkov and P. M. Echenique
J. Phys. Rev. B 67 (2003) 235423
B. Hellsing
conference proceedings: Foundations of Probability and Physics-2 (2003) p.263
A. Eiguren, B. Hellsing, E. V. Chulkov and P. M. Echenique E. V. Chulkov
J. Electr. Spectr. Rel. Phen. 129⁄2-3 (2003) 111
B. Hellsing, A. Eiguren, F. Reinert, G. Nicolay, E. V. Chulkov, V. M. Silkin, S. Hufner and P. M. Echenique E. V. Chulkov
J. Electr. Spectr. Rel. Phen. 129⁄2-3 (2003) 97
H.S. Domingos, P.D. Bristowe, J. Carlsson and B. Hellsing
Comp. Mater. Sci. (in press).
J.Carlsson, B. Hellsing, H.S. Domingos and P.D. Bristowe,
Surface Science 532(2003)351.
E. V. Chulkov, J. Kliewer, R. Berndt, V. M. Silkin, B. Hellsing, S. Crampin and P. M. Echenique
Phys. Rev. B 68(2003)195422.
J. Carlsson, H.S. Domingos, P.D. Bristowe and B. Hellsing
Phys. Rev. Lett.91(2003)165506.
H. Domingos, J. Carlsson, P. Bristow, and B.Hellsing
Interface Sci. 12(2004)227.
V. Chis and B. Hellsing
Phys. Rev. Lett. 94(2004)226103.
V. Lindberg and B.Hellsing
J.Phys: Condens. Matter, 17 (2005) S1075.
Surface Science 593(2005)12, B. Hellsing, A. Eiguren, E. V. Chulkov and P. M. Echenique
Surface Science 600(2006)6 V. Lindberg, T. Petersson and B. Hellsing
M. Breitholtz, V. Chis, B. Hellsing, S.-Å. Lindgren and L. Wallden, Physical Review B 75(2007)155403
J. Phys.: Condens. Matter (in press), V. Chis, B. Hellsing, G. Benedek, M. Bernasconi and J.P. Toennies
Conference: NANO-7/ECOSS-21. Lund, Sweden, June 2002.
Namur, Belgium, June 27-29 2002.
University of Växjö, Växjö, Sweden, June 1-6 2003.
Baroda. India, February 10-14 2004.
Erice, Sicily, Italy 20-26 July 2004.
Workshop Density Functional Theory progress”.
Chalmers University of Technology, Sweden, 23 June 2004.
Conference: Desorption Induced by Electronic Transitions 10 (DIET-10),
Susono in Japan, 8-11 November 2004.
Department of Chemistry, Tokyo University, Japan, April 2007
Conference: eph2007,
DIPC, San Sebastian, Spain, May 2007
Conference: VAS12, Erice, Italy, July 2007
Conference: ASIAN12, Beijing, China, October 2009
Conference: What about U ?, SECAM conference, EPFL-Lausanne, May 2012
Conference: CNG symposium titled: “Mini-symposium on engineering and characterization of novel materials”, Department of Micro- and Nanotechnology, DTU NANO TECH, Denmark, May 2014
Erice, Sicily, Italy 26 July - 01 August 2014.
Santa Margherita, Italy, June 2015.
Conference: Dynamical Processes at Surfaces,
Dubrovnik, Yugoslavia, September 1981, (poster).
Conference: Seminar on interactions of molecular beams with solid surfaces,
Santa Margherita, Italy, may 1982, (oral).
Conference: ECOSS-5,
Gent, Belgium, august 1982, (oral).
Conference: Seventh International Seminar on Surface Physics,
Karpacz, Polen, may 1983, (oral).
Conference: Europhysics School on Chemisorption and Surface Reactions,
Aspenäsgården, august 1983, (poster).
Conference: ECOSS-6,
York, England, April 1980, (oral).
Conference: Dynamical screening and spectroscopy of surfaces,
Trieste, Italy, June 1986, (poster).
Conference: ECOSS-9,
Lutzern, Switzerland, April 1987, (poster).
Conference: ECOSS-10,
Bologna, Italy, September 1988, (poster).
oxygen on semiconductors.”
Conference: IVC-11/ICSS-7,
Köln, Germany, September 1989, (oral).
Conference: Workshop on interaction of molecular beams and surfaces,
Hindås, Sweden, September 1990 (poster).
Conference: The 1990 seminar with the International Reference Group on Flame Modeling – Diagnostics – Kinetics,
Chalmers University of Technology, Sweden, November 1990 (oral).
Conference: Fundamental aspects of surface science,
Davos, Switzerland, June 1991, (poster).
Conference: ECOSS-12,
Stockholm, Sweden, September 1991, (oral).
in atom scattering on metal surfaces”
Conference: Molecule-Surface Interactions; Theory and Experiments,
Amsterdam, Holland, November 1991, (poster).
Conference: APS,
Indianapolis, USA, march 1992, (oral).
dissociation of O2 on metals”
Conference: Vibrations at surfaces,
St. Margherita, Italy, June 1993, (oral)
Conference: ECOSS-13,
Warwick, England, September 1993, (poster).
Conference: The Role of Negative Ion Resonances ,
Birmingham, England, November 1994, (oral).
Conference: Chemical Reactions at Surfaces ,
Ventura, USA, January 1995, (poster).
Conference: DQPSS’95 ,
Osaka, Japan, September 1995, (oral).
Conference: Ultrafast Surface Dynamics ,
Ascona, Switzerland, march 1997, (oral).
Conference: Dynamics at Surfaces (Gordon conference) ,
Andover, USA, august 1997, (poster).
Conference: VIth European Conference on Surface Crystallography ,
La grande Motte, France, may 1998, (poster).
Conference: Fundamental Aspects of Surface Science: Elementary Processes in Surface Reactions ,
Acquafredda di Maratea, Italy, June 1998, (poster).
Conference: VIII International Workshop on Ion Beam Surface Diagnostics,
Uzhgorod, Ukraine, august 1998, (oral).
Conference: American Physical Society Meeting,
Atlanta, USA, march 1999, (oral).
Conference: Dynamics at Interfaces,
Hjortviken, Sweden, June 1999, (poster).
Conference: Rutgers-Chalmers Symposium,
Chalmers, Sweden, 2000, (oral).
Conference: Ultrafast Surface Dynamics,
University of Basque Country, Spain, July 2001, (poster).
Conference: ICSFS-11,
Marseilles, France, July 2002, (oral).
Conference: 46th IUVSTAWorkshop & 5th International Symposium on Ultrafast Surface Dynamics,
Abashiri, Hokkaido, Japan, May 2006 (oral).
Conference: 3S07,
Les Arc-2000, France, Mars 2007 (oral).
Workshop: Low dimesional physics, NordForsk network meeting,
Hindåsgården, Hindås, Sweden, Mars 2007 (oral)
Conference: 20th International Workshop on Inelastic Ion-Surface Collisions (IISC-20)
16 21 February 2014, Wirrina Cove, South Australia (oral)
Conference: 21th International Workshop on Inelastic Ion-Surface Collisions (IISC-21)
18 23 October 2015, San Sebastian, Spain (oral)