Quantum heat transfer: a Born-Oppenheimer method.

We develop a Born-Oppenheimer-type formalism for the description of quantum thermal transport across hybrid nanoscale objects. Our formalism is suitable for treating heat transfer in the off-resonant regime, where, e.g., the relevant vibrational modes of the interlocated molecule are high relative to typical bath frequencies, and at low temperatures when tunneling effects dominate. A general expression for the thermal energy current is accomplished in the form of a generalized Landauer formula. In the harmonic limit this expression reduces to the standard Landauer result for heat transfer. In the presence of nonlinearities, multiphonon effects are realized.