1. Proximity-induced superconductivity in (Bi$_{1-x}$Sb$_x$)$_2$Te$_3$ topological-insulator nanowires
- Author
-
Bai, Mengmeng, Wei, Xian-Kui, Feng, Junya, Luysberg, Martina, Bliesener, Andrea, Lippertz, Gertjan, Uday, Anjana, Taskin, Alexey A., Mayer, Joachim, and Ando, Yoichi
- Subjects
Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed Matter - Materials Science ,Condensed Matter - Strongly Correlated Electrons ,Condensed Matter - Superconductivity - Abstract
When a topological insulator is made into a nanowire, the interplay between topology and size quantization gives rise to peculiar one-dimensional states whose energy dispersion can be manipulated by external fields. In the presence of proximity-induced superconductivity, these 1D states offer a tunable platform for Majorana zero modes. While the existence of such peculiar 1D states has been experimentally confirmed, the realization of robust proximity-induced superconductivity in topological-insulator nanowires remains a challenge. Here, we report the realization of superconducting topological-insulator nanowires based on (Bi$_{1-x}$Sb$_x$)$_2$Te$_3$ (BST) thin films. When two rectangular pads of palladium are deposited on a BST thin film with a separation of 100--200 nm, the BST beneath the pads is converted into a superconductor, leaving a nanowire of BST in-between. We found that the interface is epitaxial and has a high electronic transparency, leading to a robust superconductivity induced in the BST nanowire. Due to its suitable geometry for gate-tuning, this platform is promising for future studies of Majorana zero modes., Comment: 33 pages total; 22 pages of main text with 4 figures, 11 pages of supplementary information with 8 figures. This version of the article has been accepted for publication, after peer review, but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections
- Published
- 2021
- Full Text
- View/download PDF