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arXiv · 2602.22788

Magnetoresistance Oscillations in Few-Layer NbSe2 in Superconducting Fluctuation Regime

Abstract

Quantum interference phenomena in superconductors, such as Josephson interference and Little-Parks oscillations, serve as powerful probes of phase coherence, symmetry breaking and vortex dynamics. However, they are typically observed in well-defined mesoscopic structures, and their behavior in the two-dimensional limit remains largely unexplored. Here, we report periodic magnetoresistance oscillations, superconducting interference patterns, and interfering diode effect in unpatterned few-layer NbSe2. These phenomena emerge exclusively within the superconducting fluctuation regime of thin samples, consistent with the enhanced anomalous metallic behavior of atomically thin NbSe2. The non-monotonic temperature dependence of both the oscillation amplitude and the diode efficiency can be captured by a model in which thermally activated vortices traverse intrinsic supercurrent loops. Our results reveal that the observed interference phenomena originate from the lost of global phase coherence, providing a new route to accessing interference effects in unpatterned superconductors.

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Xiaolong Yin, Congzhe Cao, Yibin Feng, Kenji Watanabe, Takashi Taniguchi, Jiawei Mei, Qi-Kun Xue, Shuo-Ying Yang. 2026-02-26. Magnetoresistance Oscillations in Few-Layer NbSe2 in Superconducting Fluctuation Regime. https://doi.org/10.1103/rtxc-6tvs

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