Thermal conductivity of nonequilibrium carriers

We present a theoretical analysis of the thermal conductivity of charge carriers in semiconductors under nonequilibrium conditions due to an applied electric field. The theory is based on a correlation-function formalism which directly relates this kinetic coefficient to four spectral densities involving carrier velocity and energy flux fluctuations. Monte Carlo calculations performed for the cases of p-Si and n-GaAs give an evidence of a strong dependence of the thermal conductivity on increasing electric fields.