Fermi Surface Evolution Across Multiple Charge Density Wave Transitions in ErTe3

TL;DR

This study uses ARPES to explore how the Fermi surface of ErTe3 changes across multiple charge density wave transitions, revealing two distinct incommensurate CDW gaps and their temperature dependence.

Contribution

It provides detailed experimental insights into the evolution of the Fermi surface and the nature of multiple CDW gaps in ErTe3, highlighting their incommensurate nesting vectors.

Findings

Two incommensurate CDW gaps identified at 175 meV and 50 meV.

Fermi surface and gaps show temperature-dependent behavior.

Distinct nesting vectors associated with each CDW.

Abstract

The Fermi surface (FS) of ErTe3 is investigated using angle-resolved photoemission spectroscopy (ARPES). Low temperature measurements reveal two incommensurate charge density wave (CDW) gaps created by perpendicular FS nesting vectors. A large Delta_1 = 175 meV gap arising from a CDW with c* - q_CDW1 ~ 0.70(0) c* is in good agreement with the expected value. A second, smaller Delta_2 = 50 meV gap is due to a second CDW with a* - q_CDW2 ~ 0.68(5) a*. The temperature dependence of the FS, the two gaps and possible interaction between the CDWs are examined.