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

Hayate Kunitsu; Iori Ishiguro; Natsuki Mitsuishi; Shunsuke Tsuda; Koichiro Yaji; Zehao Wang; Pengcheng Dai; Yoichi Yamakawa; Hiroshi Kontani; Takahiro Shimojima

arXiv · 2603.18672

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

Hayate Kunitsu·Iori Ishiguro·Natsuki Mitsuishi·Shunsuke Tsuda·Koichiro Yaji·Zehao Wang·Pengcheng Dai·Yoichi Yamakawa·Hiroshi Kontani·Takahiro Shimojima

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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.

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Hayate Kunitsu, Iori Ishiguro, Natsuki Mitsuishi, Shunsuke Tsuda, Koichiro Yaji, Zehao Wang, Pengcheng Dai, Yoichi Yamakawa, Hiroshi Kontani, Takahiro Shimojima. 2026-03-19. Fermi surface of Kagome metal CsCr$_3$Sb$_5$ observed by laser photoemission microscopy. https://arxiv.org/abs/2603.18672

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