Vector magneto-optical magnetometer based on the resonant all-dielectric gratings with highly anisotropic iron-garnet films

TL;DR

This paper introduces a highly sensitive vector magnetometer utilizing resonant dielectric gratings and anisotropic iron-garnet films, capable of measuring all three magnetic field components with high spatial resolution and sensitivity.

Contribution

It presents a novel magnetometer design that enhances magneto-optical response and enables simultaneous measurement of all magnetic field components with improved resolution.

Findings

Magnetometer achieves sensitivity up to 100 pT/Hz$^{1/2}$.

Dielectric resonant grating enhances response tenfold.

Simultaneous measurement of three magnetic field components.

Abstract

A sensitive vector magnetometry with high spatial resolution is important for various practical applications, such as magnetocardiography, magnetoencephalography, explosive materials detection and many others. We propose a magnetometer based on the magnetic iron-garnet film possessing a very high magnetic anisotropy, placed in the rotating external magnetic field. Each of the measured magnetic field spatial components produces different temporal harmonics in the out-of-plane magnetization dependence. The dielectric resonant grating placed on the top of an ultrathin film enhanced the magneto-optical response 10 times which makes it possible to achieve 10 times higher spatial resolution in the perpendicular to the film direction. The reported magneto-optical magnetometer allows one to measure simultaneously all three spatial components of the magnetic field with high spatial resolution and sensitivity up to 100 pT/Hz$^{1/2}$.