Proximity-induced superconductivity in a topological crystalline insulator
Proximity-induced superconductivity in a topological crystalline insulator
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DOI：
10.1103/physrevb.100.241402
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发表时间：
2019-03
影响因子：
3.7
通讯作者：
B. Rachmilowitz;He Zhao;Hong Li;Alexander Lafleur;J. Schneeloch;R. Zhong;G. Gu;I. Zeljkovic
中科院分区：
文献类型：
--
作者：
B. Rachmilowitz;He Zhao;Hong Li;Alexander Lafleur;J. Schneeloch;R. Zhong;G. Gu;I. Zeljkovic
超导拓扑晶体绝缘体（TCI）预计将拥有受晶体对称性保护的新拓扑相，但现有材料不足以适合表面研究。为了在典型 TCI SnTe 表面诱导超导性，我们使用分子束外延生长 SnTe 异质结构和高 ${T}_{c}$ 超导体 Fe(Te,Se)，利用“缓冲”层桥接 SnTe 和 Fe(Te,Se) 之间的大晶格失配。使用低温扫描隧道显微镜和光谱学，我们测量了 SnTe 表面的显着光谱间隙，并通过其对温度和磁场的依赖性证明了其超导起源。我们的工作为超导 TCI 中出现的拓扑现象的原子尺度研究提供了一个平台。
Superconducting topological crystalline insulators (TCIs) are predicted to host new topological phases protected by crystalline symmetries, but available materials are insufficiently suitable for surface studies. To induce superconductivity at the surface of a prototypical TCI SnTe, we use molecular beam epitaxy to grow a heterostructure of SnTe and a high-${T}_{c}$ superconductor Fe(Te,Se), utilizing a ``buffer'' layer to bridge the large lattice mismatch between SnTe and Fe(Te,Se). Using low-temperature scanning tunneling microscopy and spectroscopy, we measure a prominent spectral gap on the surface of SnTe, and demonstrate its superconducting origin by its dependence on temperature and magnetic field. Our work provides a platform for atomic-scale investigations of emergent topological phenomena in superconducting TCIs.