Lawrence Berkeley National Laboratory
Onset of a Two-Dimensional Superconducting Phase in a Topological-Insulator-Normal-Metal Bi1-xSbx/Pt Junction Fabricated by Ion-Beam Techniques
- Author(s): Qu, DX
- Teslich, NE
- Dai, Z
- Chapline, GF
- Schenkel, T
- Durham, SR
- Dubois, J
- et al.
Published Web Locationhttps://doi.org/10.1103/PhysRevLett.121.037001
© 2018 American Physical Society. Inducing superconductivity in a topological insulator can lead to novel quantum effects. However, experimental approaches to turn a topological insulator into a superconductor are limited. Here, we report on superconductivity in topological insulator Bi0.91Sb0.09 induced via focused ion-beam deposition of a Pt thin film. The superconducting phase exhibits a Berezinski-Kosterlitz-Thouless transition, demonstrative of its two-dimensional character. From the in-plane upper critical field measurements, we estimate the superconducting thickness to be ∼17 nm for a 5.5-μm-thick sample. Our results provide evidence that the interface superconductivity could originate from the surface states of Bi0.91Sb0.09.