Correlated carrier dynamics in a superconducting van der Waals heterostructure

TL;DR

This paper investigates charge carrier dynamics in a novel 2D superconducting heterostructure of MoS2 and NbSe2, revealing a percolative transition and long-range correlations through conductance fluctuation analysis.

Contribution

It provides new insights into the phase transition behavior and correlated carrier dynamics in 2D superconducting heterostructures using fluctuation spectroscopy.

Findings

Superconducting transition is percolative.

Presence of non-Gaussian fluctuations indicating long-range correlations.

Different phases across the transition are characterized by noise analysis.

Abstract

The study of Berezinskii-Kosterlitz-Thouless transitions in clean, layered two-dimensional superconductors promises to provide insight into a host of novel phenomena like re-entrant vortex-dynamics, underlying unconventional metallic phases, and topological superconductivity. In this letter, we report the study of charge carrier dynamics in a novel 2-dimensional superconducting van der Waals heterostructure comprising monolayer MoS2 and few-layer NbSe2 (15 nm). Using low-frequency conductance fluctuation spectroscopy, we show that the superconducting transition in the system is percolative. We present a phenomenological picture of different phases across the transition correlating with the evaluated noise. The analysis of the higher-order statistics of fluctuation reveals non-Gaussian components around the transition indicative of long-range correlation in the system.