Memory Effect in Magnetic Nanowire Arrays

TLDR

Magnetic nanowire arrays exhibit a memory effect arising from strong dipole interactions among the wires. The authors propose a novel, extremely low‑cost EMP detection scheme based on this memory effect. The array records the peak magnetic field after the field is removed, and first‑order reversal curve measurements of switching field distributions were used to reconcile experimental observations with theory.

Abstract

A memory effect has been demonstrated in magnetic nanowire arrays. The magnetic nanowire array has the ability to record the maximum magnetic field that the array has been exposed to after the field has been turned off. The origin of the memory effect is the strong magnetic dipole interaction among the nanowires. Switching field distributions among nanowires has been studied with a first-order reversal curve technique to elucidate the discrepancy between the experimental result and the theoretical explanation. Based on the memory effect, a novel and extremely low cost EMP detection scheme is proposed.