Abstract: We show that a current-carrying coherent electron conductor can be treated as an effective bosonic energy reservoir involving different types of electron-hole pair excitations. For weak electron-boson coupling, hybrid energy transport between nonequilibrium electrons and bosons can be described by a Landauer-like formula. This allows for unified account of a variety of heat transport problems in hybrid electron-boson systems. As applications, we study the non-reciprocal heat transport between electrons and bosons, thermoelectric current from a cold-spot, and electronic cooling of the bosons. Our unified framework provides an intuitive way of understanding hybrid energy transport between electrons and bosons in their weak coupling limit. It opens the way of nonequilibrium reservoir engineering for efficient energy control between different quasi-particles at the nanoscale.

Key words: electron-hole pair, hybrid energy transport, nanojunction, electron-phonon interaction