Energy-transfer rate in a double-quantum-well system due to Coulomb coupling

Abstract

We study the energy-transfer rate for electrons in a double-quantum-well structure, where the layers are coupled through screened Coulomb interactions. The energy-transfer rate between the layers (similar to the Coulomb drag effect in which the momentum transfer rate is considered) is calculated as functions of electron densities, interlayer spacing, the temperature difference of the 2DEGs, and the electron drift velocity in the drive layer. We employ the full wave vector and frequency dependent random-phase approximation at finite temperature to describe the effective interlayer Coulomb interaction. We find that the collective modes (plasmons) of the system play a dominant role in the energy transfer rates. The contribution of optical phonons to the transfer rates through the phonon mediated Coulomb coupling mechanism has also been considered.