Experimental Observation of Topological Superconductivity and Majorana Zero Modes on beta-Bi2Pd Thin Films

TL;DR

This study reports the direct observation of topological superconductivity and Majorana zero modes in beta-Bi2Pd thin films, providing a promising platform for quantum computing applications.

Contribution

It provides experimental evidence of topologically nontrivial superconductivity and Majorana zero modes in beta-Bi2Pd films, advancing the understanding of topological quantum states.

Findings

Majorana zero modes observed at magnetic vortices

Superconducting gap larger on surface due to Dirac-fermion effects

Superconductivity and MZMs resistant to nonmagnetic defects

Abstract

Using a cryogenic scanning tunneling microscopy, we report the observation of topologically nontrivial superconductivity on a single material of \beta-Bi2Pd films grown by molecular beam epitaxy. The superconducting gap associated with spinless odd-parity pairing opens on the surface and appears much larger than the bulk one due to the Dirac-fermion enhanced parity mixing of surface pair potential. Majorana zero modes (MZMs), supported by such superconducting states, are identified at magnetic vortices. The superconductivity and MZMs exhibit resistance to nonmagnetic defects, characteristic of time-reversal-invariant topological superconductors. Our results demonstrate a simple platform to generate, manipulate and braid MZMs for quantum computation.