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arXiv · 2502.10972

Density-dependent spin susceptibility and effective mass in monolayer MoSe2

Chang Liu·Tongtong Jia·Zheng Sun·Yu Gu·Fan Xu·Kenji Watanabe·Takashi Taniguchi·Jinfeng Jia·Shiyong Wang·Xiaoxue Liu·Tingxin Li
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Abstract

Atomically thin MoSe2 is a promising platform for investigating quantum phenomena due to its large effective mass, high crystal quality, and strong spin-orbit coupling. In this work, we demonstrate a triple-gate device design with bismuth contacts, enabling reliable ohmic contact down to low electron densities, with a maximum Hall mobility of approximately 22,000 cm2/Vs. Low-temperature transport measurements illustrate metal-insulator transitions, and density-dependent quantum oscillation sequences. Enhanced spin susceptibility and density-dependent effective mass are observed, attributed to interaction effects and valley polarization. These findings establish monolayer MoSe2 as a versatile platform for further exploring interaction-driven quantum states.

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Chang Liu, Tongtong Jia, Zheng Sun, Yu Gu, Fan Xu, Kenji Watanabe, Takashi Taniguchi, Jinfeng Jia, Shiyong Wang, Xiaoxue Liu, Tingxin Li. 2025-02-16. Density-dependent spin susceptibility and effective mass in monolayer MoSe2. https://doi.org/10.1088/2053-1583%2Fadce18

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