Magnetic field optical sensors using Ce:YIG single crystals as a Faraday element

In this paper, a new type of magnetic field optical sensor based on creation of the Faraday effect by rotation magnetization of Ce:YIG single crystals was studied. A large linear magnetic birefringence (LMB, the Cotton-Mouton effect) of Δn = −1.7 × 10−4 was observed in Ce:YIG crystal at the wavelength of 1.3 μm, and it was found that this effect is the main origin of the reduction of the sensitivity and its large temperature dependence. The validity of the method of utilizing a pair of Ce:YIG crystals with an azimuth angle of 90° in the optical axis is demonstrated as a method of improving these phenomena