Tunable vortex Majorana modes controlled by strain in homogeneous LiFeAs

Abstract

The iron-based superconductors (FeSCs) have recently emerged as a promising single-material Majorana platform by hosting isolated Majorana zero modes (MZMs) at relatively high temperatures. To further verify its Majorana nature and move forward to build topological quantum qubits, it is highly desirable to achieve tunability for MZMs on homogeneous FeSCs. Here, with an in-situ strain device, we can controllably create MZMs on the homogeneous surface of stoichiometric superconductor LiFeAs by altering its chemical potential. The evolution of discrete energy modes inside a strained vortex is found to mimic exactly as the predicted topological vortex case, proving the Majorana nature of emerging zero modes of vortex. More importantly, our work provides a controllable method for MZM in a homogeneous FeSC, and such achievement of tunability of MZMs in the FeSC Majorana-material platform is an important step towards their application in topological quantum computation.