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arXiv · 2111.03786

Tunable vortex Majorana modes controlled by strain in homogeneous LiFeAs

Wenyao Liu·Quanxin Hu·Xiancheng Wang·Yigui Zhong·Fazhi Yang·Lingyuan Kong·Lu Cao·Geng Li·Kozo Okazaki·Takeshi Kondo·Changqing Jin·Fuchun Zhang·Jinpeng Xu·Hong-Jun Gao·Hong Ding
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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 qubit, 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 inducing a topological phase transition. The evolution of discrete energy modes inside a strained vortex is found to mimics exactly as the predicted topological vortex case, proving the Majorana nature of emerging zero modes of vortex. Such tunability of MZMs in a homogeneous superconductor is an important step toward their application in topological quantum computation.

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Wenyao Liu, Quanxin Hu, Xiancheng Wang, Yigui Zhong, Fazhi Yang, Lingyuan Kong, Lu Cao, Geng Li, Kozo Okazaki, Takeshi Kondo, Changqing Jin, Fuchun Zhang, Jinpeng Xu, Hong-Jun Gao, Hong Ding. 2022-11-19. Tunable vortex Majorana modes controlled by strain in homogeneous LiFeAs. https://doi.org/10.1007/s44214-022-00022-w

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