Optimizing Vortex Magnetic Tunnel Junctions for Advanced Magnetic Sensing

Magnetic tunnel junctions (MTJs) are vital in spintronics, offering multifunctional capabilities in memory, RF generation, and sensing. Recent efforts aim to enhance magnetoresistance, reduce intrinsic noise, and improve magnetic switching precision by minimizing hysteresis. In this work, we explore the development of vortex MTJs, leveraging topological protection to stabilize the magnetic state. Our objective is to enhance sensing linearity and minimize hysteresis without sacrificing magnetoresistance. We investigate how free layer thickness and junction diameter impact performance metrics such as dynamic range, sensitivity, and vortex formation stability. Through micromagnetic simulations, we model spin relaxation dynamics across various initial conditions, corroborating our predictions with experimental validation. Our findings reveal the interplay between structure and performance, providing insights for optimizing vortex MTJs for ultrasensitive sensing. This research was supported by the National Institute of Biomedical Imaging and Bioengineering (NIBIB) of the National Institutes of Health under Award Number UG3EB034695. The content presented here reflects the views of the authors and not necessarily those of the NIH.