Observation of Enhanced Faraday Effect in Eu-Doped Ce:YIG Thin Films
Han-Xu 晗旭 Zhang 张, Sen-Yin 森寅 Zhu 朱, Jin 劲 Zhan 湛, Xian-Jie 先杰 Wang 王, Yi 一 Wang 王, Tai 泰 Yao 姚, N. I. Mezin, Bo Song
Abstract
Ce:YIG thin films are taken as an ideal candidate for magneto-optical devices with giant Faraday effect in the near-infrared range, but it is hindered by a limited Ce 3+ /Ce 4+ ratio and a high saturation driving field. To address this issue, Eu doping can increase the Faraday rotation angle by ∼ 40% to 1.315 × 10 4 deg/cm and decrease the saturation driving field by ∼ 38% to 1.17 kOe in Eu 0.75 Ce 1 Y 1.25 Fe 5 O 12 compared to Ce 1 Y 2 Fe 5 O 12 pristine. The mechanism is attributed to the conversion of Ce 4+ to Ce 3+ and the weakening of ferrimagnetism by Eu doping. This work not only provides strategies for improving Ce 3+ /Ce 4+ ratio in Ce:YIG, but also develops (Eu,Ce):YIG with a promising Faraday rotation angle for magneto-optical devices.