Space- and time-resolved Seebeck and Nernst voltages in laser-heated permalloy/gold microstructures

Abstract

Thermoelectric effects in microstructured permalloy (Py)/Au wires are investigated using space- and time-resolved measurements based on scanning focused laser heating. Supported by numerical simulations of the temperature distribution, we identify two major contributions to the laser-induced signals: (i) the Seebeck effect due to thermocouples of Py/Au and (ii) the anomalous Nernst effect (ANE) in Py with a coefficient of N ANE ≈ 1.6 μ V / K. ANE-based magnetic imaging of magnetic domains and magnetization reversal is demonstrated with a lateral resolution on the μm scale. © 2013 American Institute of Physics.