Universal superconductivity phase diagram for pressurized tetradymite topological insulators

Shu Cai, S. K. Kushwaha, Jing Guo, Vladimir A. Sidorov, Congcong Le, Yazhou Zhou, Honghong Wang, Gongchang Lin, Xiaodong Li, Yanchuan Li, Ke Yang, Aiguo Li, Qi Wu, Jiangping Hu, Robert J. Cava, and Liling Sun

Phys. Rev. Materials 2, 114203 – Published 13 November 2018

Abstract

We show that two different superconducting phases exist at high pressures in the optimized tetradymite topological insulators $B i_{2} T e_{2} Se$ (BTS) and $B i_{1.1} S b_{0.9} T e_{2} S$ (BSTS). The superconducting phases emerge at structural phase transitions; the first at $\sim 8.4 GPa$ for BTS and $\sim 12.4 GPa$ for BSTS, and the second at 13.6 GPa for BTS and 20.4 GPa, for BSTS. Electronic structure calculations show that these phases do not have topological character. Comparison of our results with prior work on $B i_{2} S e_{3}$ , $B i_{2} T e_{3}$ , and ${(Bi, Sb)}_{2} {(Se, Te)}_{3}$ allows us to uncover a universal phase diagram for pressure-induced superconductivity in tetradymites, providing a basis for understanding the relationships between topological behavior, crystal structure, and superconductivity for these materials.

Received 4 September 2018

DOI:https://doi.org/10.1103/PhysRevMaterials.2.114203

Physics Subject Headings (PhySH)

Topological materials

Pressure effects

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Shu Cai^1,4, S. K. Kushwaha^2,9, Jing Guo¹, Vladimir A. Sidorov³, Congcong Le^1,5, Yazhou Zhou¹, Honghong Wang^1,4, Gongchang Lin^1,4, Xiaodong Li⁶, Yanchuan Li⁶, Ke Yang⁷, Aiguo Li⁷, Qi Wu¹, Jiangping Hu^1,4, Robert J. Cava^2,*, and Liling Sun^1,4,8,†

¹Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
²Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA
³Institute for High Pressure Physics, Russian Academy of Sciences, 142190 Troitsk, Moscow, Russia
⁴University of Chinese Academy of Sciences, Beijing 100190, China
⁵Kavli Institute of Theoretical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
⁶Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
⁷Shanghai Synchrotron Radiation Facilities, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, China
⁸Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
⁹National High Magnetic Field Laboratory, LANL, Los Alamos, New Mexico 87504, USA