Giant magneto-impedance (GMI) magnetometers

Abstract

This chapter is about recent advances in giant magneto-impedance (GMI) magnetometer development. The emphasis is put on their performances in terms of equivalent magnetic noise. We first present the physical principles and outline the model of the GMI effect. Next, we establish the relation between the GMI sensing element and the associated electronic conditioning circuits, thus providing expressions for the performances of the device. Our approach is pragmatic and aimed at scientists and engineers concerned with sensitive magnetic measurements. It is hoped that our presentation of the topic will be useful to workers in the field who wish to compare GMI to other magnetic sensors.