Significant Magnon Contribution to Heat Transfer in Nickel Nanowires

Abstract

Magnons, quantized spin waves arising from collective excitations of spins, are typically considered negligible contributors to heat transfer. However, recent studies on low-dimensional magnetic materials have challenged this notion, revealing significant magnon-mediated heat transport. The underlying physics behind this phenomenon, however, remains poorly understood. In this study, we observed a significant reduction in heat transfer in nickel nanowires under the influence of a magnetic field. Our theoretical model revealed a substantial magnon contribution of up to 30% to nanowire heat transfer. The reduction in heat transfer under a magnetic field stemmed from a drastic decrease in the magnon mean free path (MFP). This decrease in MFP was primarily attributed to suppressing long wavelength magnons with a longer MFP. Our findings provide deeper insights into heat transfer mechanisms in nanoscale ferromagnetic materials and offer valuable guidance for the design of future spintronic devices.