Vortex-driven superconducting diode effect in asymmetric multilayer heterostructures

TL;DR

This study uses simulations to uncover how vortex dynamics and layer stacking order in asymmetric multilayer superconductors cause the diode effect, offering ways to control or suppress it for device applications.

Contribution

It provides a microscopic understanding of the vortex-driven superconducting diode effect in multilayer heterostructures and demonstrates control via stacking order modifications.

Findings

SDE arises from vortex dynamics influenced by Lorentz forces.

Layer stacking order critically affects the presence of SDE.

Changing stacking order can suppress the superconducting diode effect.

Abstract

The superconducting diode effect (SDE), characterized by nonreciprocal critical currents, has attracted growing attention due to its potential applications in quantum technologies and energy-efficient devices. In this work, we explore the microscopic mechanism of the SDE by simulating asymmetric multilayer heterostructures within time-dependent Ginzburg-Landau theory. We systematically vary the layer thickness, external magnetic field and stacking order in a trilayer structure composed of niobium, vanadium, and tantalum, which share a similar structure to that in the pioneering experimental work, to clarify the role of vortex dynamics. Our simulations reveal a pronounced SDE originating from the interplay of Lorentz forces and asymmetric vortex dynamics, which strongly depend on layer stacking order. Besides, by simply changing the stacking order of the constituent layers, the SDE can be entirely suppressed. These findings offer insights into the microscopic mechanisms of the SDE and provide a feasible approach for controlling and eliminating the SDE in practical superconducting devices.