dc effect in ferromagnetic resonance: Evidence of the spin-pumping effect?

Abstract

Direct current voltage appears across and in plane of a ferromagnetic multilayer experiencing ferromagnetic resonance. We have investigated the dc voltage simultaneously generated with the excitation of the uniform mode of magnetization precession in ferromagnetic∕normal-metal∕ferromagnetic trilayers with different spacer-layer materials. The generated voltage strongly depends on the chemical nature and the thickness of the normal-metal spacer as well as on the microwave incident power. This dc voltage might be correlated with the spin-pumping effect recently predicted.