Large spin-to-charge conversion at the two-dimensional interface of transition metal dichalcogenides and permalloy

TL;DR

This study demonstrates large spin-to-charge conversion at the interface of transition metal dichalcogenides and permalloy, showing potential for efficient spintronic devices through interface engineering at room temperature.

Contribution

It provides the first direct measurement of spin-to-charge conversion at TMD/ferromagnet interfaces, revealing a correlation with spin-orbit coupling strength.

Findings

Large spin-to-charge conversion observed at room temperature.

Spin mixing conductance and Rashba efficiency scale with TMD spin-orbit coupling.

The Rashba efficiency parameter ranges between -0.54 and -0.76 nm.

Abstract

Spin-to-charge conversion is an essential requirement for the implementation of spintronic devices. Recently, monolayers of semiconducting transition metal dichalcogenides (TMDs) have attracted considerable interest for spin-to-charge conversion due to their high spin-orbit coupling and lack of inversion symmetry in their crystal structure. However, reports of direct measurement of spin-to-charge conversion at TMD-based interfaces are very much limited. Here, we report on the room temperature observation of a large spin-to-charge conversion arising from the interface of Ni$_{80}$Fe$_{20}$ (Py) and four distinct large area ($\sim 5\times2$~mm$^2$) monolayer (ML) TMDs namely, MoS$_2$, MoSe$_2$, WS$_2$, and WSe$_2$. We show that both spin mixing conductance and the Rashba efficiency parameter ($\lambda_{IREE}$) scales with the spin-orbit coupling strength of the ML TMD layers. The $\lambda_{IREE}$ parameter is found to range between $-0.54$ and $-0.76$ nm for the four monolayer TMDs, demonstrating a large spin-to-charge conversion. Our findings reveal that TMD/ferromagnet interface can be used for efficient generation and detection of spin current, opening new opportunities for novel spintronic devices.