Anomalous Nernst effect in Pr0.5Sr0.5CoO3

Abstract

We report the anomalous Nernst effect (ANE) in polycrystalline metallic perovskite Pr0.5Sr0.5CoO3. The transverse Seebeck coefficient (Sxy) was measured at selected temperatures for magnetic fields up to H = 50 kOe and also as a function of temperature at two selected magnetic fields (H = 2 and 10 kOe). While Sxy increases linearly with H above the Curie temperature (TC ∼ 229 K), it changes non-linearly at low fields in the ferromagnetic state and exhibits hysteresis similar to magnetization. Linear extrapolation of the high field Sxy vs H graph to zero field gives Sxy = 0.46 µV/K at 175 K. It is found that the manganite counterpart Pr0.5Sr0.5MnO3 having a similar hole content exhibits much smaller Sxy than Pr0.5Sr0.5CoO3 in a field of 2 kOe. Our analysis suggests that the ANE in this sample is most likely due to asymmetric skew scattering of charge carriers.