Anisotropic magnetocaloric effect in gadolinium thin films: Magnetization measurements and acoustic detection

Abstract

In this letter, it is demonstrated the ability of the magnetoacoustic technique in detecting the magnetocaloric effect in gadolinium thin films (1.0 μm and 3.0 μm thick), which is not accessible through conventional temperature sensors because of the reduced mass of the samples. The method, which detects the direct effect of the sample temperature variation, proved to be sensitive to the anisotropy of the films, making possible for the investigation of the anisotropic magnetocaloric effect. Magnetization measurements were also carried out, and from these measurements both the adiabatic temperature and the isothermal entropy variations were calculated. The acoustically detected magnetocaloric effect shows very good agreement with these calculations.