Logo der Universität Wien
You are here:>University of Vienna >Faculty of Physics>Vienna Computational Materials Laboratory

U(1)×SU(2) Gauge-Invariance Made Simple for Density Functional Approximations

A talk by Dr. Stefano Pittalis, CNR - Istituto Nanoscienze, Modena, Italy

DATE / TIME: Monday, December 12th 2016, 4:00 p.m.
LOCATION: Seminar Room DB gelb 09, TU Wien, "Freihaus"‐building, 9th floor

ABSTRACT: A non-relativistic density-functional approach that includes spin-orbit couplings self-consistently is an appealing framework to develop a unified first-principles computational approach for non-collinear magnetism, spintronics, and spinorbitronics. The basic variables of this framework include the (paramagnetic) particle- and spin-currents besides the particle- and spin-densities. The corresponding exchange-correlation energy functional is invariant under local U(1)×SU(2)-gauge transformations. This functional must be approximated to enable practical applications but, contrary to the standard case, it has been a long-standing challenge to find simple building blocks ideally suited to deal with realistic atomistic inhomogeneities. Here, we propose a non-empirical resolution based on the analysis of the short-range behavior of the exchange-hole function and related quantities. Novel prototypical approximations will be outlined.

 

 

VIENNA COMPUTATIONAL MATERIALS LABORATORY

Sensengasse 8/12
A-1090 Vienna
AUSTRIA
T: +43-1-4277-51401
F: +43-1-4277-9514
E-Mail
University of Vienna | Universitätsring 1 | 1010 Vienna | T +43-1-4277-0
Lastupdate: 07.10.2015 - 16:42