Observation of edge supercurrent in topological antiferromagnet MnBi 2 Te 4 -based Josephson junctions
- Enze Zhang
- Zi-Ting Sun
- Zehao Jia
- Jinshan Yang
- Jingyi Yan
- Linfeng Ai
- Ying-Ming Xie
- Yuda Zhang
- Xue-Jian Gao
- Xian Xu
- Shanshan Liu
- Qiang Ma
- Chaowei Hu
- Xufeng Kou
- Jin Zou
- Ni Ni
- Kam Tuen Law
- Shaoming Dong
- Faxian Xiu
2025-05-14
Hybridizing superconductivity with topology and magnetism attracts growing interest in condensed matter physics. Here, we present our findings on the measurement of supercurrent induced in an intrinsic antiferromagnetic topological insulator MnBi 2 Te 4 . By constructing a MnBi 2 Te 4 proximity Josephson junction, we observed an anomalously large period of the Fraunhofer patterns, indicating a strong Josephson coupling state. As the MnBi 2 Te 4 thickness is reduced, a distinct asymmetric edge supercurrent emerges, aligning consistently with the observed oscillatory junction magnetoresistance. Leveraging this large asymmetric edge supercurrent, we have realized a nonvolatile Josephson diode device with programmable polarity, achieved through training with an out-of-plane magnetic field. Theoretical calculations substantiate that these behaviors are attributed to the interference between the highly asymmetric topological edge channel–mediated supercurrent induced in MnBi 2 Te 4 . Our study establishes this system as a promising avenue for investigating topological superconductivity, chiral Majorana edge modes, and advanced functionality device applications.