Transverse magnetothermoelectric effects are studied in Permalloy thin films grown on MgO and GaAs substrates and compared to those grown on suspended SiN(x) membranes. The transverse voltage along platinum strips patterned on top of the Permalloy films is measured versus the external magnetic field as a function of the angle and temperature gradients. After the identification of the contribution of the planar and anomalous Nernst effects, we find an upper limit for the transverse spin Seebeck effect, which is several orders of magnitude smaller than previously reported.

A SiNx based suspended platform has been developed that allows for the simultaneous measurement of the transport coefficients, namely the resistivity ρ, thermopower , and thermal conductivity κ. We describe the calorimeter fabrication and the characterization of the set-up required to enable quantitative experiments. The temperature distribution of a typical device is numerically simulated to verify the spatial homogeneity. The method is illustrated for PdxNi1−x and CoxFe1−x ferromagnetic thin films. We employ a novel double bridge technique that allows for an accurate determination of the thermal conductivity.

Electroresistance has become a stimulating research topic because of its potential applications in next‐generation nonvolatile memory technology. Here, an electroresistance‐like behavior of the antiperovskite Mn3GaC compound around the antiferromagnetic–intermediate phase transition is reported. A high sensing current significantly decreases the fraction of the antiferromagnetic phase of higher resistivity relative to the intermediate phase of lower resistivity upon warming, showing a resistivity change up to 50%. Through extensive studies of the resistivity at different sample locations and of the magnetization under applied current, it is unambiguously shown that this electroresistance‐like behavior originates from the local Joule heating of the sample due to high‐resistive lead contacts and not from an intrinsic effect. These findings open an available avenue to explore electroresistance‐like behavior by achieving phase coexistence of a high‐ and low‐resistivity phase under the driving force of local Joule heating.

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Resistivity ρ, thermopower S, and thermal conductivity κ were measured simultaneously on a set of CoFe alloy films. Variation of the Co-content xCo allows for a systematic tuning of the Fermi level through the band structure, and the study of the interplay between electronic and magnetic contributions to the transport coefficients. While band structure and magnon effects in ρ and κ are rather weak, they turn out to be very significant in S. The evolution of Mott and magnon drag contributions to S is traced between the two limiting cases of pure Fe and pure Co. In addition, we find an interesting sign change of the magnon drag.

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Investigating the thermoelectric properties of ferromagnets is important for the development of future microelectronic devices for efficient energy conversion purposes. Ferromagnetic Mn5Ge3Cx thin films with a Curie temperature up to TC=450K well above room temperature are potential candidates for spintronic applications by integration into CMOS heterostructures. In this work, the thermoelectric power, in particular, the anomalous Nernst effect (ANE), has been investigated experimentally for magnetron sputtered thin films on sapphire (112¯0) substrates. The ANE gradually increases with increasing carbon content x up to a maximum value obtained for x=0.8 in line with the earlier investigations of the magnetization and anomalous Hall effect. The ANE is strongly enhanced by a factor three compared to the parent Mn5Ge3 compound. However, for x=0.8, we observe a clear deviation of the calculated ANE from the measured values.