  Investigating the non-linear transport regime in a quantum dot heat engine
described by the Anderson-Holstein model, it is shown that a finite
electron-phonon interaction leads to a charge induced phonon generation that
stimulates a phonon current even in the absence of a thermal gradient. This
gives rise to the non-linear phonon Peltier effect which shows a non-trivial
dependence on varying the electron-phonon interaction. Utilizing the reversal
of phonon currents via charge induced phonon accumulation, we demonstrate that
the heat engine surprisingly can be cooled when coupled to a hot reservoir. In
further exploring possibilities that can arise from this effect, we propose a
charge-induced phonon switching mechanism.
