Hard Superconducting Gap in PbTe Nanowires

作者：Yichun 益淳 Gao 高, Wenyu Song, Shuai Yang, Zehao 泽昊 Yu 于, Ruidong 睿东 Li 李, Wentao 文韬 Miao 苗, Yuhao 禹灏 Wang 王, Fangting 芳婷 Chen 陈, Zuhan 祖汗 Geng 耿, Lining 利宁 Yang 杨, Zezhou 泽洲 Xia 夏, Xiao 硝 Feng 冯, Yunyi Zang, Lin 琳 Li 李, Runan Shang, Qi-Kun 其坤 Xue 薛, Ke 珂 He 何, Hao Zhang · 发表于：Chinese Physics Letters · 年份：2024 · DOI：10.1088/0256-307x/41/3/038502 · 被引用次数：13 · 研究领域：Topological Materials and Phenomena、Physics of Superconductivity and Magnetism、Quantum many-body systems

Semiconductor nanowires coupled to a superconductor provide a powerful testbed for quantum device physics such as Majorana zero modes and gate-tunable hybrid qubits. The performance of these quantum devices heavily relies on the quality of the induced superconducting gap. A hard gap, evident as vanishing subgap conductance in tunneling spectroscopy, is both necessary and desired. A hard gap has been achieved and extensively studied before in III–V semiconductor nanowires (InAs and InSb). In this study, we present the observation of a hard superconducting gap in PbTe nanowires coupled to a superconductor Pb. The gap size Δ is ∼ 1 meV (maximally 1.3 meV in one device). Additionally, subgap Andreev bound states can also be created and controlled through gate tuning. Tuning a device into the open regime can reveal Andreev enhancement of the subgap conductance. These results pave the way for diverse superconducting quantum devices based on PbTe nanowires.