Magnetic field sensors using VO2/Fe3O4nanoparticle devices

Massood Tabib-Azar

doi:10.1088/1361-6528/aceb6c

Magnetic field sensors using VO₂/Fe₃O₄nanoparticle devices

Nanotechnology. 2023 Oct 4;34(50). doi: 10.1088/1361-6528/aceb6c.

Author

Massood Tabib-Azar¹

Affiliation

¹ Electrical and Computer Eng. Department, University of Utah, Salt Lake City, UT 84112, United States of America.

PMID: 37506680
DOI: 10.1088/1361-6528/aceb6c

Abstract

We combined the metal-insulator transition (MIT) properties of VO₂and the magnetic properties of Fe₃O₄to realize a magnetometer with very large nonlinearity and switching characteristics. VO₂, Fe₃O₄nanoparticles, and a conductive binder (silver paint) were mixed and drop-casted onto two-terminal gap junction devices. The device's current-voltage characteristics exhibited current-switching behavior related to MIT in VO₂which changed with the external magnetic field. The magnetoresistance and magnetostriction in Fe₃O₄both contributed to the field sensitivity of the sensor. Sensitivities as high as 1 A nT^-1(or 50.8 V T^-1with a current bias) were observed near the MIT voltage. The resulting minimum detectable signal was 20 pT/SQRT(Hz).

Keywords: biomimetic; magnetometer; metal-insulator transition (MIT); neuromorphic.