2014/01/01 by Pierre Darancet, Andrew J. Millis, Chris A. Marianetti
Physics and Astronomy · #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.90.045134
5 pages, 3 figures
arxiv created 2014/01/01 · arxiv updated 2015/06/18
Using density functional theory with added on-site interactions (DFT+U), we study the electronic structure of bulk, monolayer, and bilayer of the layered transition-metal dichalcogenide 1T-TaS2. We show that a two-dimensional spin--(1)/(2) Mott-phase exists for the monolayer in the charge-density wave state (CDW) and that such a phase is systematically destroyed by packing of the distorted layers leading to a one dimensional metal for bulk, CDW-distorted TaS2. The latter finding is in contrast with previous DMFT predictions --disagreement we explain by the weak effective interaction felt by the electrons in the CDW state. Experimental observations of insulating behavior may arise from disorder due to stacking faults.