Chemical-Potential-Dependent Superconducting Spectroscopy on Bi2Te3/NbSe2 Heterostructures

Pengyu Hu; Chun Yu Wan; Qiaoyan Yu; Chen Qian; Yisheng Gu; Xian Du; Xuhui Ning; Tingwen Miao; Shi Chen; Zihao Ma; Hao Yang; Hemian Yi; Weijiong Chen; Xiaoxue Liu; Liang Liu; Dandan Guan; Yaoyi Li; Shiyong Wang; Canhua Liu; Sangen Zhao; Fulin Wang; Junwei Liu; Hao Zheng; Jinfeng Jia

arXiv · 2610.14627

Chemical-Potential-Dependent Superconducting Spectroscopy on Bi2Te3/NbSe2 Heterostructures

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Abstract

High-resolution scanning tunneling spectroscopy performed at dilution refrigerator temperatures was employed to investigate the superconducting properties of topological insulator/superconductor (Bi2Te3/NbSe2) heterostructures. Coherence peaks with inner kinks or inner peaks, deviating from the conventional single s-wave spectral line shape, were observed in both 5 quintuple-layer (5QL) and 7QL Bi2Te3 thin films. Based on the combination of chemical-potential-dependent spectroscopic measurements and model simulations, we conclude that these spectral features arise from contributions of bulk and surface states in Bi2Te3 by selectively proximity-coupled to a single superconducting gap from NbSe2, rather than inheriting the complicated superconductor's order parameter of NbSe2.

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Pengyu Hu, Chun Yu Wan, Qiaoyan Yu, Chen Qian, Yisheng Gu, Xian Du, Xuhui Ning, Tingwen Miao, Shi Chen, Zihao Ma, Hao Yang, Hemian Yi, Weijiong Chen, Xiaoxue Liu, Liang Liu, Dandan Guan, Yaoyi Li, Shiyong Wang, Canhua Liu, Sangen Zhao, Fulin Wang, Junwei Liu, Hao Zheng, Jinfeng Jia. 2026-10-10. Chemical-Potential-Dependent Superconducting Spectroscopy on Bi2Te3/NbSe2 Heterostructures. https://arxiv.org/abs/2610.14627

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