Quantitative separation of the anisotropic magnetothermopower and planar Nernst effect by the rotation of an in-plane thermal gradient

• Published in: Scientific reports Vol. 7; no. 1; p. 40586
• Main Authors: Reimer, Oliver, Meier, Daniel, Bovender, Michel, Helmich, Lars, Dreessen, Jan-Oliver, Krieft, Jan, Shestakov, Anatoly S., Back, Christian H., Schmalhorst, Jan-Michael, Hütten, Andreas, Reiss, Günter, Kuschel, Timo
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 17.01.2017; Nature Publishing Group
• Subjects: 639/925; 639/925/930/12; Anisotropy; Humanities and Social Sciences; Magnetic fields; multidisciplinary; Phase shift; Science; Temperature; Temperature effects; Thin films
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep40586

A thermal gradient as the driving force for spin currents plays a key role in spin caloritronics. In this field the spin Seebeck effect (SSE) is of major interest and was investigated in terms of in-plane thermal gradients inducing perpendicular spin currents (transverse SSE) and out-of-plane thermal gradients generating parallel spin currents (longitudinal SSE). Up to now all spincaloric experiments employ a spatially fixed thermal gradient. Thus, anisotropic measurements with respect to well defined crystallographic directions were not possible. Here we introduce a new experiment that allows not only the in-plane rotation of the external magnetic field, but also the rotation of an in-plane thermal gradient controlled by optical temperature detection. As a consequence, the anisotropic magnetothermopower and the planar Nernst effect in a permalloy thin film can be measured simultaneously. Thus, the angular dependence of the magnetothermopower with respect to the magnetization direction reveals a phase shift, that allows the quantitative separation of the thermopower, the anisotropic magnetothermopower and the planar Nernst effect.