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arXiv · 1910.08331

Novel self-epitaxy for inducing superconductivity in the topological insulator (Bi1-xSbx)2Te3

Mengmeng Bai·Fan Yang·Martina Luysberg·Junya Feng·Andrea Bliesener·Gertjan Lippertz·A. A. Taskin·Joachim Mayer·Yoichi Ando
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Abstract

Using the superconducting proximity effect for engineering a topological superconducting state in a topological insulator (TI) is a promising route to realize Majorana fermions. However, epitaxial growth of a superconductor on the TI surface to achieve a good proximity effect has been a challenge. We discovered that simply depositing Pd on thin films of the TI material (Bi$_{1-x}$Sb$_x$)$_2$Te$_3$ leads to an epitaxial self-formation of PdTe$_2$ superconductor having the superconducting transition temperature of ~1 K. This self-formed superconductor proximitizes the TI, which is confirmed by the appearance of a supercurrent in Josephson-junction devices made on (Bi$_{1-x}$Sb$_x$)$_2$Te$_3$. This self-epitaxy phenomenon can be conveniently used for fabricating TI-based superconducting nanodevices to address the superconducting proximity effect in TIs.

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Mengmeng Bai, Fan Yang, Martina Luysberg, Junya Feng, Andrea Bliesener, Gertjan Lippertz, A. A. Taskin, Joachim Mayer, Yoichi Ando. 2019-10-18. Novel self-epitaxy for inducing superconductivity in the topological insulator (Bi1-xSbx)2Te3. https://doi.org/10.1103/physrevmaterials.4.094801

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