Fast, sensitive magnetic-field sensors based on the Faraday effect in YIG

Abstract

Magnetic-field sensors based on the Faraday effect in ferrimagnetic iron garnets are investigated in terms of their sensitivity, speed, and directionality. Signal-to-noise measurements at 80 Hz on small (typically 5-mm-diameter*3-mm-long) samples of yttrium iron garnet (YIG) yield noise equivalent magnetic fields of 10 nT/ square root Hz. Frequency-response measurements exhibit virtually flat response to approximately 700 MHz.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>