Temperature dependence of magnetic field sensors using (Cd1−<i>x</i>Mn<i>x</i>)Te and a light-emitting-diode light source

Abstract

Verdet constants and optical transmissions of (Cd1−xMnx)Te solid solutions are determined as a function of Mn concentration, temperature, and wavelength. The sensitivity or modulation depth of magnetic field sensors using Faraday rotation in magneto-optical materials is analyzed using an effective Verdet constant. The effective Verdet constant is defined by a weighted average of normal Verdet constants. The average is over the spectral profile of the light source and is weighted by the intensity of transmitted light through the material and filter. The temperature dependence of the sensitivity in the sensors using (Cd,Mn)Te in various Mn concentrations and light-emitting-diode light sources is discussed.