Gate-controlled superconducting switch in GaSe/NbSe$_2$ van der Waals heterostructure

TL;DR

This paper demonstrates a gate-controlled superconducting switch in a 2D heterostructure, enabling reversible switching between superconducting and normal states through high-energy electron injection and ferroelectric polarization effects.

Contribution

It introduces a novel superconducting switch using GaSe/NbSe₂ heterostructure with electric field modulation and ferroelectric polarization, advancing 2D superconductor device technology.

Findings

High-energy electron injection modulates superconductivity.

Ferroelectric GaSe enhances device performance.

Reversible switching between superconducting and normal states.

Abstract

The demand for low-power devices is on the rise as semiconductor engineering approaches the quantum limit and quantum computing continues to advance. Two-dimensional (2D) superconductors, thanks to their rich physical properties, hold significant promise for both fundamental physics and potential applications in superconducting integrated circuits and quantum computation. Here, we report a gate-controlled superconducting switch in GaSe/NbSe$_2$ van der Waals (vdW) heterostructure. By injecting high-energy electrons into NbSe$_2$ under an electric field, a non-equilibrium state is induced, resulting in significant modulation of the superconducting properties. Owing to the intrinsic polarization of ferroelectric GaSe, a much steeper subthreshold slope and asymmetric modulation are achieved, which is beneficial to the device performance. Based on these results, a superconducting switch is realized that can reversibly and controllably switch between the superconducting and normal state under an electric field. Our findings highlight a significant high-energy injection effect from band engineering in 2D vdW heterostructures combining superconductors and ferroelectric semiconductors, and demonstrate the potential applications for superconducting integrated circuits.