Magnonic spin Joule heating and rectification effects

Abstract

Nonlinear devices, such as transistors, enable contemporary computing technologies. We theoretically investigate nonlinear effects, bearing a high fundamental scientific and technical relevance, in magnonics with emphasis on superconductor-ferromagnet hybrids. Accounting for finite magnon chemical potential, we theoretically demonstrate magnonic spin-Joule heating, the spin analogue of conventional electronic Joule heating. Besides suggesting a key contribution to magnonic heat transport in a broad range of devices, it provides insights into the thermal physics of non-conserved bosonic excitations. Considering a spin-split superconductor self-consistently, we demonstrate its interface with a ferromagnetic insulator to harbor large tunability of spin and thermal conductances. We further demonstrate hysteretic rectification I-V characteristics in this hybrid, where the hysteresis results from the superconducting state bistability.

Magnon-Cooparons in magnet-superconductor hybrids

“…An injected charge current predominantly converts into conventional spinless supercurrent [22]. Due to such reasons, several advantages of magnet-superconductor heterostructures realized in various concepts and devices are still dominated by the quasiparticle properties [7,[28][29][30][31][32][33][34][35]. The exploiting of spinfull Cooper pairs for new physics and devices has been im-peded by the complex hybrids needed to generate them and the difficulty of controlling them.…”