All-electrical magnetic vortex array sensing

Abstract

Vortex sensing magnetometers based on arrays of soft magnetic dots are good candidates for high-resolution and accurate spatial magnetic-field estimation. When the arrays are laid out along different spatial directions they can perform tensor gradiometry allowing the measurement of field components and their spatial derivatives as a function of orientation. Detection is based on using spin-polarized currents to counteract vortex displacements or to excite vortex oscillation modes triggered by magnetic-field application. Sensor linearization, field detection range and conditions to obtain large sensitivity electronic compatibility and scalability are discussed.

Response of a Bell–Bloom Magnetometer to a Magnetic Field of Arbitrary Direction

“…In order to realize the effective detection of an external magnetic field, many kinds of magnetometers, like the fluxgate [ 1 ], Hall probe [ 2 ], proton magnetometer [ 3 ], soft ferromagnetic dot arrays [ 4 ], superconducting quantum interference device (SQUID) [ 5 , 6 ], and atomic magnetometer [ 7 , 8 ], appeared one after another. Of these magnetometers, the SQUID is the most sensitive magnetometer which has been commercially produced, but it needs a cumbersome refrigeration device.…”