Surface states around a vortex in topological superconductors: Intersection of a surface and a vortex

TL;DR

This study numerically investigates how Majorana surface states are suppressed around vortices in three-dimensional topological superconductors, revealing the robustness of vortex line states and potential experimental signatures.

Contribution

It demonstrates the suppression of surface Majorana states near vortices and their resilience along vortex lines in topological superconductors, providing new insights into their spatial behavior.

Findings

Majorana surface states are suppressed around vortices.

Vortex line Majorana states are robust against surface interruption.

Suppression can be observed via STM/STS energy dependence.

Abstract

We numerically show that the zero-energy Majorana surface states are suppressed around a vortex in the three-dimensional topological superconductors such as Cu$_{x}$Bi$_{2}$Se$_{3}$ and Sn$_{1-x}$In$_{x}$Te. On the other hand, the zero-energy Majorana bound states along the vortex line are robust against cut by the surface. The suppression of the surface bound states is similar to that with a magnetic impurity on the surface of the topological insulator. The suppression of the surface-bound states around a vortex can be observed as the unconventional energy dependence of imaging of the scanning tunneling microscopy/spectroscopy.