Pressure-driven dome-shaped superconductivity in topological insulator GeBi2Te4

Chenchen Liu; Yiping Gao; Can Tian; Chuang Jiang; Chengcheng Zhu; Xinyue Wu; Xiaoli Huang; Tian Cui

doi:10.1088/1361-648X/ad2e24

Pressure-driven dome-shaped superconductivity in topological insulator GeBi₂Te₄

J Phys Condens Matter. 2024 Mar 7;36(22). doi: 10.1088/1361-648X/ad2e24.

Authors

Chenchen Liu¹, Yiping Gao¹, Can Tian¹, Chuang Jiang¹, Chengcheng Zhu¹, Xinyue Wu¹, Xiaoli Huang¹, Tian Cui^{1

2}

Affiliations

¹ State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, People's Republic of China.
² School of Physical Science and Technology, Ningbo University, Ningbo 315211, People's Republic of China.

PMID: 38417156
DOI: 10.1088/1361-648X/ad2e24

Abstract

The discovery of new superconductors based on topological insulators always captures special attention due to their unique structural and electronic properties. High pressure is an effective way to regulate the lattice as well as electronic states in the topological insulators, thus altering their electronic properties. Herein, we report the structural and electrical transport properties of the topological insulator GeBi₂Te₄by using high-pressure techniques. The synchrotron x-ray diffraction revealed that GeBi₂Te₄underwent two structural phase transitions fromR-3m(phase I) toC2/m(phase II) and then intoIm-3m(phase III). Superconductivity was observed at 6.6 GPa to be associated with the first structural phase transition. The superconducting transition temperatureT_creached a maximum value of 8.4 K, accompanied by theR_Hsign changing from negative to positive at 14.6 GPa, then gradually decreased with increasing pressure in phase III, showing a dome-shaped phase diagram. The present results provide a platform for understanding the interplay between the crystal structure and superconductivity by the regulation of pressure in the topological insulator materials.

Keywords: dome-shaped superconductivity; high-pressure; structural phase transition; topological insulators.