Uniform magnetic fields in density-functional theory
Abstract
We construct a density-functional formalism adapted to uniform external magnetic fields that is intermediate between conventional Density Functional Theory and Current-Density Functional Theory (CDFT). In the intermediate theory, which we term LDFT, the basic variables are the density, the canonical momentum, and the paramagnetic contribution to the magnetic moment. Both a constrained-search formulation and a convex formulation in terms of Legendre--Fenchel transformations are constructed. Many theoretical issues in CDFT find simplified analogues in LDFT. We prove results concerning -representability, Hohenberg--Kohn-like mappings, existence of minimizers in the constrained-search expression, and a restricted analogue to gauge invariance. The issue of additivity of the energy over non-interacting subsystems, which is qualitatively different in LDFT and CDFT, is also discussed.
Cite
@article{arxiv.1709.10400,
title = {Uniform magnetic fields in density-functional theory},
author = {Erik I. Tellgren and Andre Laestadius and Trygve Helgaker and Simen Kvaal and Andrew M. Teale},
journal= {arXiv preprint arXiv:1709.10400},
year = {2018}
}