Nanoscale three-dimensional magnetic sensing with a probabilistic nanomagnet driven by spin-orbit torque

TL;DR

This paper introduces a nanoscale, all-electric vector magnetic field sensor using a probabilistic nanomagnet driven by spin-orbit torque, demonstrating high sensitivity and potential for miniaturized magnetic sensing applications.

Contribution

The work presents an experimental demonstration of a nanoscale magnetic sensor based on a probabilistic nanomagnet driven by spin-orbit torque, enabling all-electric vector magnetic field detection.

Findings

Achieved sensitivities of 1.02%, 1.09%, and 3.43%/Oe for Hx, Hy, and Hz.

Demonstrated a 200 x 200 nm^2 nanomagnet as a sensing element.

Minimum detectable field could be as low as 1 μT with sufficient pulse events.

Abstract

Detection of vector magnetic fields at nanoscale dimensions is critical in applications ranging from basic material science, to medical diagnostic. Meanwhile, an all-electric operation is of great significance for achieving a simple and compact sensing system. Here, we propose and experimentally demonstrate a simple approach to sensing a vector magnetic field at nanoscale dimensions, by monitoring a probabilistic nanomagnet's transition probability from a metastable state, excited by a driving current due to SOT, to a settled state. We achieve sensitivities for Hx, Hy, and Hz of 1.02%/Oe, 1.09%/Oe and 3.43%/Oe, respectively, with a 200 x 200 nm^2 nanomagnet. The minimum detectable field is dependent on the driving pulse events N, and is expected to be as low as 1 uT if N = 3 x 10^6.