Probing the temperature-dependent magnetic anisotropy and longitudinal spin Seebeck effect in Y3Fe5O12

Y3Fe5O12 (YIG) has attracted growing interest since a large Longitudinal Spin Seebeck Effect (LSSE) was discovered in this material. However, the origin of the LSSE and its temperature dependence are not well understood. We report here, the temperature dependence of the effective magnetic anisotropy field (HK) and LSSE voltage (VLSSE) of single crystal YIG, measured using the radio-frequency transverse susceptibility (TS) and LSSE techniques, respectively. VLSSE is found to vary from 40 nV to 97 nV from 100 to 300 K, which is consistent with the previously reported experimental results. Interestingly, we find the temperature dependence of HK resembles that of VLSSE in the high temperature regime (100 – 300 K), with the sudden changes in both VLSSE and HK at ∼175 K. Our results indicate the possible role of magnetic anisotropy in the LSSE in YIG and provide important insights into improving LSSE in magnetic materials through manipulating their magnetic anisotropy.