Thermal conductance of thin film YIG determined using Bayesian statistics

Thin film YIG (Y₃Fe₅O₁₂) is a prototypical material for experiments on thermally generated pure spin currents and the spin Seebeck effect. The 3ω method is an established technique to measure the cross-plane thermal conductance of thin films, but cannot be used in YIG/GGG (Ga₃Gd₅O₁₂) systems in its standard form. We use two-dimensional modeling of heat transport and introduce a technique based on Bayesian statistics to evaluate measurement data taken from the 3ω method. Our analysis method allows us to study material systems that have not been accessible with the conventionally used 3ω analysis. Temperature-dependent thermal conductance data of thin film YIG are of major importance for experiments in the field of spin caloritronics. Here we show data between room temperature and 10 K for films covering a wide thickness range as well as the magnetic field effect on the thermal conductance between 10 and 50 K.