(a) Model for representing the MCE measurement setup. The sample is coupled to the bath and the thermometer by the thermal conductances and , respectively. Schematics of the changes in H and as functions of (b) t and (c) μ0 H.
Schematic drawing for (a) the sample with thermometer and (b) the probe setup. (c) Relaxation curve at 300 K measured by applying a heating current to the film thermometer as a heater.
Magnetoresistance of (a) the Au film thermometer deposited on a sapphire substrate and (c) the Au0.18Ge0.82 film thermometer deposited on a quartz substrate. (Inset) Temperature dependence of R without magnetic field. Artificial temperature change caused by the magnetoresistance of (b) the Au film thermometer and (d) the Au0.18Ge0.82 film thermometer.
(a) H dependence of on the Gd sample measured in pulsed magnetic fields up to 7.2 T at various . The arrow corresponds to . (b) vs . (Solid circles) measured in the pulsed fields. (Open squares) the data from Ref. 18 which were estimated by the specific heats measured in steady field. The data from Ref. 18 are interpolated from 7.5 T to 7.2 T. (Inset) and as a function of . (c) vs H up to 55 T at = 295 K (blue line), red dashed curve: the calculated data by molecular field approximation and Eq. (3) , black dotted curve: the artificial temperature change caused by the MR in Au film thermometer.
(a) Temperature dependence of entropy in polycrystalline Gd at 2 T, 5 T, and 7.2 T determined by the isentropic shifts of entropies at zero field by . (b) Temperature dependence of the specific heats in Gd at 2 T, 5 T, and 7.2 T (open marks: estimated from MCEs, solid curves: measured in zero fields 18 ).
Field dependence of in Au0.18Ge0.82 film grown on the GGG crystal at the temperature of 6–30 K (solid line). (Open circles) Field induced adiabatic temperature change of . 10 The arrow corresponds to .
Entropy vs temperature in several magnetic fields. (Solid curves) Entropies estimated from specific heats at 0 T, 4 T, and 10 T. (Dashed line) Entropies calculated from the crystal field model explained by Dai et al. 25 (Open symbols) Entropies estimated from . (Inset) C H − T curves at 0 T, 4 T, and 10 T.
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