Program

I.1 -- Invited, IWTCP-3

Date: Monday, 27 July 2015

Time: 10h40 - 11h15

Density Functional Theory and Fermi Surfaces

Mukunda P. Das

Department of Theoretical Physics, RSPE, The Australian National University, Canberra, ACT 6201, Australia

Density functional theory (DFT) is considered as the standard model for low energy physics by its great achievement in the field of condensed matter science. The theory is based on theorems by Hohenberg and Kohn that the ground state properties of an interacting many-body system can be described exactly by a functional of the one particle density. Unfortunately this functional remains unknown in the exact sense. However, a number of approximate functionals are used over the past several decades to a variety of condensed matter problems. In this talk I shall describe ground state properties of metals by using the DFT. Particular attention will be paid to a special property of a metal, i.e. its Fermi surface. Generally it is believed by the DFT practitioners that the Fermi surface is a ground state property, therefore, DFT in its Kohn-Sham (local density version) is capable of producing a physical Fermi surface. In fact, there seems to be some controversy about this perception, where Fermi surface is not a-priori obviously a ground state property. I shall present some rigorous arguments towards the correct understanding of this predicament.

Presenter: Mukunda P. Das