Thermal rectification and spin-spin coupling of nonreciprocal localized and surface modes

We study the rectification of near-field radiative heat transfer between two InSb nanoparticles due to the presence of nonreciprocal surface modes in a nearby InSb sample when an external magnetic field is applied and its dependence on the magnetic field strength. We reveal the spin-spin coupling mechanism of the localized particle resonances and the surface mode resonances which is substantiated by the directional heat flux in the given setup. We discuss further the interplay of the frequency shift, the propagation length, and local density of states on the strength and directionality of the rectification as well as the nonreciprocal heating effect of the nanoparticles.