paper

Pressure induced re-emergence of superconductivity in superconducting topological insulator Sr0.065Bi2Se3

arXiv:1604.08293 · doi:10.1103/PhysRevB.93.144514

Abstract

The recent-discovered Sr $_{x}$ Bi $_{2}$ Se $_{3}$ superconductor provides an alternative and ideal material base for investigating possible topological superconductivity. Here, we report that in Sr $_{0.065}$ Bi $_{2}$ Se $_{3}$ , the ambient superconducting phase is gradually depressed upon the application of external pressure. At high pressure, a second superconducting phase emerges at above 6 GPa, with a maximum $T_{c}$ value of $\sim$ 8.3 K. The joint investigations of the high-pressure synchrotron x-ray diffraction and electrical transport properties reveal that the re-emergence of superconductivity in Sr $_{0.065}$ Bi $_{2}$ Se $_{3}$ is closely related to the structural phase transition from ambient rhombohedral phase to high-pressure monoclinic phase around 6 GPa, and further to another high-pressure tetragonal phase above 25 GPa.

13 pages, 4 figures