Room-temperature tunable tunneling magnetoresistance in Fe3GaTe2/WSe2/Fe3GaTe2 van der Waals heterostructures

TL;DR

This study demonstrates room-temperature tunable tunneling magnetoresistance in a van der Waals heterostructure, enabling adjustable magnetic sensing functionalities through electrical control at room temperature.

Contribution

It reports the first observation of electrically tunable TMR at room temperature in a full vdW Fe3GaTe2/WSe2/Fe3GaTe2 heterostructure, with sign and magnitude control.

Findings

TMR of 340% at 2 K and 50% at 300 K.

TMR magnitude and sign modulated by DC bias current.

Room-temperature tunable TMR achieved in vdW heterostructure.

Abstract

The exceptional properties of two-dimensional (2D) magnet materials present a novel approach to fabricate functional magnetic tunnel junctions (MTJ) by constructing full van der Waals (vdW) heterostructures with atomically sharp and clean interfaces. The exploration of vdW MTJ devices with high working temperature and adjustable functionalities holds great potential for advancing the application of 2D materials in magnetic sensing and data storage. Here, we report the observation of highly tunable room-temperature tunneling magnetoresistance through electronic means in a full vdW Fe3GaTe2/WSe2/Fe3GaTe2 MTJ. The spin valve effect of the MTJ can be detected even with the current below 1 nA, both at low and room temperatures, yielding a tunneling magnetoresistance (TMR) of 340% at 2 K and 50% at 300 K, respectively. Importantly, the magnitude and sign of TMR can be modulated by a DC bias current, even at room temperature, a capability that was previously unrealized in full vdW MTJs. This tunable TMR arises from the contribution of energy-dependent localized spin states in the metallic ferromagnet Fe3GaTe2 during tunnel transport when a finite electrical bias is applied. Our work offers a new perspective for designing and exploring room-temperature tunable spintronic devices based on vdW magnet heterostructures.