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Asymmetric edge supercurrents in MoTe₂ Josephson junctions.

ABSTRACT: To investigate the higher order topology in MoTe₂, the supercurrent interference phenomena in Nb/MoTe₂/Nb planar Josephson junctions have been systematically studied. By analyzing the obtained interference pattern of the critical supercurrents and performing a comparative study of the edge-touched and untouched junctions, it's found that the supercurrent is dominated by the edges, rather than the bulk or surfaces of MoTe₂. An asymmetric Josephson effect with a field-tunable sign is also observed, indicating the nontrivial origin of the edge states. These results not only provide initial evidence for the hinge states in the higher order topological insulator MoTe₂, but also demonstrate the potential applications of MoTe₂-based Josephson junctions in rectifying the supercurrent.

SUBMITTER: Chen P

PROVIDER: S-EPMC10791112 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature

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Asymmetric edge supercurrents in MoTe2 Josephson junctions.

Chen Pingbo P Wang Jinhua J Wang Gongqi G Ye Bicong B Zhou Liang L Wang Le L Wang Jiannong J Zhang Wenqing W Chen Weiqiang W Mei Jiawei J He Hongtao H

Nanoscale advances 20231221 2

To investigate the higher order topology in MoTe2, the supercurrent interference phenomena in Nb/MoTe2/Nb planar Josephson junctions have been systematically studied. By analyzing the obtained interference pattern of the critical supercurrents and performing a comparative study of the edge-touched and untouched junctions, it's found that the supercurrent is dominated by the edges, rather than the bulk or surfaces of MoTe2. An asymmetric Josephson effect with a fi ...[more]

PMID: 38235086

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