A Microwave Magnetometer

Faraday rotation in ferrites at microwave frequencies is applied experimentally to a new magnetometer technique expected to attain extreme sensitivity. The microwave output voltage is linearly, related to the magnetic field. Sensitivity is a function of microwave carrier level, length and initial permeability of the ferrite rotator. Experimental response curves are given for two different rotator lengths. Magnetic increments of the order of one gamma have been detected. The prospect of attaining the extreme sensitivity inherent in the microwave magnetometer principle suggests the magnetic detection possibilities of a micro-magnetometer.