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arXiv · 2211.01609

Josephson Effect in NbS$_{2}$ van der Waals Junctions

Chuanwen Zhao·Xin Yi·Qiao Chen·Chengyu Yan·Shun Wang
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Abstract

Van der Waals (vdW) Josephson junctions can possibly accelerate the development of advanced superconducting device that utilizes the unique properties of two-dimensional (2D) transition metal dichalcogenide (TMD) superconductors such as spin-orbit coupling, spin-valley locking. Here, we fabricate vertically stacked NbS$_{2}$/NbS$_{2}$ Josephson junctions using a modified all-dry transfer technique and characterize the device performance via systematic low-temperature transport measurements. The experimental results show that the superconducting transition temperature of the NbS$_{2}$/NbS$_{2}$ Josephson junction is 5.84 K, and the critical current density reaches 3975 A/cm$^{2}$ at 2K. Moreover, we extract a superconducting energy gap $\Delta=0.58$ meV, which is considerably smaller than that expected from the single band s-wave Bardeen-Cooper-Schrieffer (BCS) model ($\Delta=0.89$ meV).

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Chuanwen Zhao, Xin Yi, Qiao Chen, Chengyu Yan, Shun Wang. 2022-11-03. Josephson Effect in NbS$_{2}$ van der Waals Junctions. https://doi.org/10.1021/acs.jpclett.2c02927

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