Magnon-mediated thermal transport in antiferromagnets: the link to momentum-resolved magnon lifetime data

Transport currents in solids decay through collisions of quasiparticles with each other and with defects or boundaries. Since information about collisional lifetimes is difficult to obtain, most calculations of transport properties rely on parameters that are not known independently. Here, we use magnon lifetime data for the two-dimensional antiferromagnet Rb2MnF4 to calculate the magnon-mediated thermal conductivity without any adjustable parameters, thereby quantifying the influence of scattering from domain boundaries on transport. Related strategies have the potential to enhance our understanding of thermal transport by electronic and phononic quasiparticles greatly.