Nanophysics

My research area is condensed matter physics, and in particular surface physics, where I perform theoretical and numerical modeling of electronic structure and chemical reactivity of small (nanometer range) adsorbed surface structures, so called quantum dots. The calculations are peformed in the context of density functional theory using the MIKA (Multigrid Instead of K-spAce) program package.

I defended my doctoral thesis (abstract) in Theoretical Physics with title 'Electronic Structure and Reactivity of Adsorbed Metallic Quantum Dots' at Växjö university in 2005. The research had been perfomed in collaboration with Prof. Bo Hellsing at the Solid State Physics group at Göteborg University, Dr. Tuomas Torsti previously at CSC - the Finnish IT centre for science and now at Rijksuniversiteit Groningen , Prof. Martti Puska at COMP, Laboratory of Physics at Helsinki university of Technology and Tomas Petersson at the Department of Physics at Växjö university.

 

 

Electronic structure of Quantum dots

We focus on the system of Na/Cu(111), where Na is adsorbed on a Cu(111) surface. Experimentally, it has been observed  that the second monolayer of Na grows via formation of one monolayer thick islands or quantum dots. The electrons within the quantum dot are confined to the surface structure by the vacuum barrier on one side and the bandgap of the Cu(111) substrate on the other side. The quantum dot behaves like an artificial atom, and the electrons therefore show corresponding quantum mechanical effects of confinement, where the discrete energy spectrum depends on the quantum dot parameters.

Calculated sosurfaces of the electron density and the local density of states for a quantum dot containing 550 electrons. (T.Torsti, V. Lindberg, M. J. Puska and B. Hellsing, Phys. Rev. B 66, 235420 (2002)).

Related publications:

Poster:

Model study of adsorbed quantum dots: Na/Cu(111)

 

 

Reactivity of adsorbed quantum dots

We focus on the process of CO adsorbtion on metallic quantum dots. We are interested in understanding how the quantum dot parameters such as height and lateral size influences the electron spectrum and thereby also the adsorbtion properties of the quantum dot.

Related publications:

  • Reactivity of Adsorbed Metallic Quantum Dots, V. Lindberg, T. Petersson and B. Hellsing, Surf. Sci. 600, 6, (2006).
  • Electronic Structure and Reactivity of adsorbed Metallic Quantum Dots (Doctoral Thesis), Växjö University Press 59, (2005). ISSN: 1404-4307, ISBN: 91-7636-451-8.
  • Metallic Quantum Dots, V. Lindberg and B. Hellsing, J. Phys. Condens. Matter 17, S1075 (2005).

 

 

MIKa- The Multigrid instead of K-space program package

MIKA is a program package for electronic structure calculations developed by Helsinki university of Technology and CSC-Centre for scientific computing in Helsinki, Finland. MIKA solves the Kohn-Sham equations of Density functional theory directly in real-space using a multigrid method.

The MIKA homepage at CSC

Related publications:

 

 

NETWORKs

IMG-Interphase Modelling Group

Nordforsk - Quantum Properties of Nanostructures

Psi-k

CETUSS - Stepping Stones

Nano materials and packaging

 

Redigera
Share Dela