Ta 5d band symmetry of 1T-TaS1.2Se0.8 in the commensurate charge-density-wave phase

Phys Rev Lett. 2003 Dec 19;91(25):256404. doi: 10.1103/PhysRevLett.91.256404. Epub 2003 Dec 18.

Abstract

We present a detailed angle-resolved photoemission study on the layered transition-metal dichalcogenide 1T-TaS1.2Se0.8 in the commensurate charge-density-wave (CDW) phase. A drastic reduction in the spectral weight along the high symmetry line GammaM, particularly around the point M, is observed when s-polarized light was used. This implies that the initial state must be symmetric with respect to a mirror plane perpendicular to the line GammaK, which is consistent with conventional band calculations in the absence of the CDW. We conclude that there is only a limited amount of modification of the electronic structure of 1T-TaS1.2Se0.8 in the commensurate CDW phase due to the CDW-related potential.