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arXiv · 2401.13072

Nonreciprocal charge transport in the titanium sesquioxide heterointerface superconductor

Peng Dong·Lijie Wang·Guanqun Zhang·Jiadian He·Yiwen Zhang·Yifan Ding·Xiaohui Zeng·Jinghui Wang·Xiang Zhou·Yueshen Wu·Wei Li·Jun Li
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Abstract

Nonreciprocal charge transport in heterostructural superconductors exhibits appealing quantum physical phenomena and holds the promising potential for superconducting circuits applications. Realizing a nonreciprocity is, however, fundamentally and technologically challenging, as it requires a material structure without a centre of inversion, which is scarce among superconducting materials. Here, we report an evidence of helical superconductivity, in which the Rashba spin-orbit coupling induces momentum-dependent superconducting gap in the inversion symmetry breaking heterointerface superconductor consisting of Mott insulating Ti$_2$O$_3$ and polar semiconducting GaN. Remarkably, the nonlinear responses emerge in the superconducting transition regime, when the magnetic field is precisely aligned in-plane orientations perpendicular to the applied current. In particular, the observed nonreciprocal supercurrent is extremely sensitive to the direction of the magnetic field for 0.5 degree, suggestive of a crossover from a symmetry breaking state to a symmetric one. Our finding not only unveils the underlying rich physical properties in heterointerface superconductors, but also provides an exciting opportunity for the development of novel mesoscopic superconducting devices.

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Peng Dong, Lijie Wang, Guanqun Zhang, Jiadian He, Yiwen Zhang, Yifan Ding, Xiaohui Zeng, Jinghui Wang, Xiang Zhou, Yueshen Wu, Wei Li, Jun Li. 2024-01-23. Nonreciprocal charge transport in the titanium sesquioxide heterointerface superconductor. https://arxiv.org/abs/2401.13072

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