Magnetoresistance Oscillations in Few-Layer NbSe2 in Superconducting Fluctuation Regime

TL;DR

This study uncovers magnetoresistance oscillations and interference effects in unpatterned few-layer NbSe2 within its superconducting fluctuation regime, highlighting phase coherence loss in atomically thin superconductors.

Contribution

It demonstrates the emergence of quantum interference phenomena in unpatterned, atomically thin NbSe2 during superconducting fluctuations, expanding understanding beyond mesoscopic structures.

Findings

Periodic magnetoresistance oscillations observed

Superconducting interference patterns identified

Interfering diode effect detected

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.