Near-field heat transfer between disordered conductors

Heat transfer mediated by near-field fluctuations of the electromagnetic field was studied. In the case of metals, the latter are dominated by Coulomb interactions between thermal fluctuations of electronic density. It was shown that an elastic scattering of electrons, leading to a diffusive propagation of density fluctuations, results in a qualitative change of the radiation law. While the heat flux between clean metals follows the Stefan-Boltzmann-like T⁴ dependence, the heat exchange between disordered conductors is significantly enhanced and scales as T³ at low temperatures.