Ground-State Degeneracies Leave Recognizable Topological Scars in the Electronic Density

Roi Baer
2010 Physical Review Letters  
In Kohn-Sham density functional theory (KS-DFT) a fictitious system of non-interacting particles is constructed having the same ground-state (GS) density as the physical system of interest. A fundamental open question in DFT concerns the ability of an exact KS calculation to spot and characterize the GS degeneracies in the physical system. In this article we provide theoretical evidence suggesting that the GS density, as a function of position on a 2D manifold of parameters affecting the
more » ... l potential, is "topologically scarred" in a distinct way by degeneracies. These scars are sufficiently detailed to enable determination of the positions of degeneracies and even the associated Berry phases. We conclude that an exact KS calculation can spot and characterize the degeneracies of the physical system.
doi:10.1103/physrevlett.104.073001 pmid:20366875 fatcat:v4frheyg6vdbrbajltlvreigz4