Observation of the giant magneto-Seebeck effect in a metastable Co50Fe50/Cu multilayer

We report the observation of the giant magneto-Seebeck (GMS) effect in an epitaxially grown Co50Fe50/Cu multilayer film with metastable bcc Cu spacers under an in-plane temperature gradient. The magnetization-dependent switching ratio of the Seebeck coefficient, GMS ratio, and switching ratio of the thermoelectric power factor reach approximately -50% and 280% at room temperature, respectively, which are higher than those previously reported in magnetic multilayers with the current-in-plane geometry. By measuring the temperature dependence of both GMS and giant magnetoresistance (GMR) effects, we found that the GMS ratio remains high at high temperatures, while the GMR ratio quickly decreases with increasing temperature, where the spin-dependent electron scattering dominantly affects the large GMS effect in the Co50Fe50/Cu multilayer.