Charge-spin conversion phenomena such as the spin Hall effect allow for the excitation of magnons in a magnetic layer by passing an electric current in an adjacent nonmagnetic conductor. We demonstrate that this current-induced modification of the magnon density generates an additional nonlinear longitudinal and transverse magnetoresistance for every magnetoresistance that depends on the magnetization. Using harmonic measurements, we evidence that these magnon creation-annihilation magnetoresistances dominate the second harmonic longitudinal and transverse resistance of thin Y3Fe5O12/Pt bilayers. Our results apply to both insulating and metallic magnetic layers, elucidating the dependence of the magnetoresistance on applied current and magnetic field for a broad variety of systems excited by spin currents.
@article{arxiv.2411.07991,
title = {Nonlinear longitudinal and transverse magnetoresistances due to current-induced magnon creation-annihilation processes},
author = {Paul Noël and Richard Schlitz and Emir Karadža and Charles-Henri Lambert and Luca Nessi and Federico Binda and Pietro Gambardella},
journal= {arXiv preprint arXiv:2411.07991},
year = {2025}
}