Power-Law Temperature Dependence of the Penetration Depth in a Topological Superconductor Due to Surface States

Tsz Chun Wu, Hridis K. Pal, Pavan Hosur, and Matthew S. Foster

Phys. Rev. Lett. 124, 067001 – Published 14 February 2020

Abstract

We study the temperature dependence of the magnetic penetration depth in a 3D topological superconductor (TSC), incorporating the paramagnetic current due to the surface states. A TSC is predicted to host a gapless 2D surface Majorana fluid. In addition to the bulk-dominated London response, we identify a $T^{3}$ power-law-in-temperature contribution from the surface, valid in the low-temperature limit. Our system is fully gapped in the bulk, and should be compared to bulk nodal superconductivity, which also exhibits power-law behavior. Power-law temperature dependence of the penetration depth can be one indicator of topological superconductivity.

Received 1 June 2019
Accepted 27 January 2020

DOI:https://doi.org/10.1103/PhysRevLett.124.067001

Physics Subject Headings (PhySH)

Meissner effect Surface states p-wave

Topological superconductors

Linear response theory

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Tsz Chun Wu¹, Hridis K. Pal², Pavan Hosur³, and Matthew S. Foster^1,4

¹Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA
²Department of Physics, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
³Texas Center for Superconductivity and Department of Physics, University of Houston, Houston, Texas 77204, USA
⁴Rice Center for Quantum Materials, Rice University, Houston, Texas 77005, USA