Remnant Fermi Surface in the Presence of an Underlying Instability in Layered <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>1</mn><mi mathvariant="italic">T</mi><mo>–</mo><mrow><msub><mrow><mi mathvariant="normal">TaS</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span>

Th. Pillo; J. Hayoz; H. Berger; M. Grioni; L. Schlapbach; P. Aebi

doi:10.1103/PhysRevLett.83.3494

Remnant Fermi Surface in the Presence of an Underlying Instability in Layered $1 T - {TaS}_{2}$

Th. Pillo, J. Hayoz, H. Berger, M. Grioni, L. Schlapbach, and P. Aebi

Phys. Rev. Lett. 83, 3494 – Published 25 October 1999

Abstract

We report high resolution angle-scanned photoemission and Fermi surface (FS) mapping experiments on the layered transition-metal dichalcogenide $1 T - {TaS}_{2}$ in the quasicommensurate (metallic) and the commensurate (insulating) charge-density-wave (CDW) phase. Instead of a nesting induced partially removed FS in the CDW phase we find a pseudogap over large portions of the FS. This remnant FS exhibits the symmetry of the one-particle normal state FS. Possibly, this Mott localization induced transition represents the underlying instability responsible for the pseudogapped FS.