Fermi surface of Kagome metal CsCr$_3$Sb$_5$ observed by laser photoemission microscopy

TL;DR

This study maps the Fermi surface of Kagome metal CsCr$_3$Sb$_5$ using laser photoemission microscopy, revealing orbital-dependent correlations and small pockets that inform understanding of its magnetic and superconducting properties.

Contribution

First detailed laser photoemission microscopy analysis of the Fermi surface in CsCr$_3$Sb$_5$, highlighting orbital-dependent effects and small Fermi surface pockets.

Findings

Identified circular and hexagonal Fermi surfaces around the BZ center.

Detected small Fermi surface pockets at the BZ boundary.

Found strong orbital dependence in Fermi surface size, especially for d$_{xz}$ orbital.

Abstract

We investigated the Fermi surface (FS) in the paramagnetic state of Kagome metal CsCr$_3$Sb$_5$ by employing a laser photoemission microscopy. We found a circular FS and two hexagonal FSs around the Brillouin zone (BZ) center. Polarization-dependent measurements further enable us to detect small FS pockets at the BZ boundary. According to the density functional theory calculations, the orbital characters of the FSs were determined from their shape and orientations. We found that the size of the FS is strongly modified for the d$_{xz}$ orbital, suggesting the orbital-dependent correlation effect. These results provide an electronic basis for exploring the interplay of antiferromagnetic/charge density wave order and possible unconventional superconductivity in this compound.