Topological Phase Transition-Induced Tri-Axial Vector Magnetoresistance in (Bi1-xInx)2Se3 Nanodevices

TL;DR

This study investigates tri-axial vector magnetoresistance in (Bi1-xInx)2Se3 nanodevices, revealing topological phase transition effects and potential for room-temperature spintronic sensors.

Contribution

It demonstrates the influence of topological phase transition on magnetoresistance in nanodevices, highlighting novel in-plane negative MR behavior near the critical point.

Findings

In-plane negative MR up to room temperature

Large out-of-plane positive MR

MR ratio of approximately -3%: -1%: 225% at 2 K

Abstract

We report the study of a tri-axial vector magnetoresistance (MR) in nonmagnetic (Bi1-xInx)2Se3 nanodevices at the composition of x = 0.08. We show a dumbbell-shaped in-plane negative MR up to room temperature as well as a large out-of-plane positive MR. MR at three directions is about in a -3%: -1%: 225% ratio at 2 K. Through both the thickness and composition-dependent magnetotransport measurements, we show that the in-plane negative MR is due to the topological phase transition enhanced intersurface coupling near the topological critical point. Our devices suggest the great potential for room-temperature spintronic applications, for example, vector magnetic sensors.