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arXiv · 2011.09357

Kagome van-der-Waals Pd3P2S8 with flat band

Abstract

With the advanced investigations into low-dimensional systems, it has become essential to find materials having interesting lattices that can be exfoliated down to monolayer. One particular important structure is a kagome lattice with its potentially diverse and vibrant physics. We report a van-der-Waals kagome lattice material, Pd3P2S8, with several unique properties such as an intriguing flat band. The flat band is shown to arise from a possible compact-localized state of all five 4d orbitals of Pd. The diamagnetic susceptibility is precisely measured to support the calculated susceptibility obtained from the band structure. We further demonstrate that Pd3P2S8 can be exfoliated down to monolayer, which ultimately will allow the possible control of the localized states in this two-dimensional kagome lattice using the electric field gating.

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Seunghyun Park, Soonmin Kang, Haeri Kim, Ki Hoon Lee, Pilkwang Kim, Sangwoo Sim, Nahyun Lee, Balamurugan Karuppannan, Junghyun Kim, Jonghyeon Kim, Kyung Ik Sim, Matthew J. Coak, Yukio Noda, Cheol-Hwan Park, Jae Hoon Kim, Je-Geun Park. 2020-11-18. Kagome van-der-Waals Pd3P2S8 with flat band. https://arxiv.org/abs/2011.09357

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