Bias Voltage Driven Tunneling Magnetoresistance Polarity Reversal in 2D Stripy Antiferromagnet CrOCl

TL;DR

This paper demonstrates voltage-controlled polarity reversal of tunneling magnetoresistance in 2D CrOCl, revealing electric field effects on magnetic states and advancing spintronic device potential.

Contribution

It provides the first systematic study of magnetoresistance in monolayer and bilayer CrOCl, showing electric field-induced phase transitions and magnetoresistance polarity reversal.

Findings

Positive magnetoresistance at low bias in antiferromagnetic phase

Reversal to negative magnetoresistance at higher bias voltages

Electric dipoles influence magnetic phase transitions

Abstract

Atomically thin materials with coupled magnetic and electric polarization are critical for developing energy-efficient and high-density spintronic devices, yet they remain scarce due to often conflicting requirements of stabilizing both magnetic and electric orders. The recent discovery of the magnetoelectric effect in the 2D stripy antiferromagnet CrOCl highlights this semiconductor as a promising platform to explore electric field effects on magnetoresistance. In this study, we systematically investigate the magnetoresistance in tunneling junctions of bilayer and monolayer CrOCl. We observe that the transition from antiferromagnetic to ferrimagnetic phases in both cases induces a positive magnetoresistance at low bias voltages, which reverses to a negative value at higher bias voltages. This polarity reversal is attributed to the additional electric dipoles present in the antiferromagnetic state, as supported by our theoretical calculations. These findings suggest a pathway for the electric control of spintronic devices and underscore the potential of 2D magnets like CrOCl in advancing energy-efficient spintronic applications.