Phonon recycling

抄録

Following an introduction to the macro-level heat recirculation pioneered by Echigo, we introduce phonon recycling, especially in nonequilibrium conditions. We review the sources of nonequilibrium (i.e., hot) phonons and their assisted and unassisted absorptions leading to electronic excitations. We then review an example of phonon recycling in high-power current circuits using heterobarriers with potentials matching with the optical phonon energy. This integrated hot-phonon absorbing barrier (HPAB) can reduce the operating temperature, the net heat generation, and the power consumption of these devices.