Negligible thermal contributions to the spin pumping signal in ferromagnetic metal–platinum bilayers”

Spin pumping by ferromagnetic resonance is one of the most common techniques to determine spin Hall angles, Edelstein lengths, or spin diffusion lengths of a large variety of materials. In recent years, there have been increasing concerns over the interpretation of these experiments, underlining that the signal could arise purely from thermoelectric effects rather than coherent spin pumping. Here, we propose a method to evaluate the presence or absence of thermal effects in spin pumping signals, by combining bolometry and spin pumping by ferromagnetic resonance measurements and comparing their timescale. Using a cavity to perform the experiments on Pt\permalloy and La0.7Sr0.3MnO3\Pt samples, we conclude on the absence at resonance of any measurable thermoelectric contribution such as the spin Seebeck and anomalous Nernst effects.

J. Appl. Phys. 127, 163907 (2020).


Posted in Research Activity.