  We demonstrate control over heat flow in an N-terminal molecular junction.
Using simple model Hamiltonians we show that the heat current through two
terminals can be tuned, switched, and amplified, by the temperature and
coupling parameters of external gating reservoirs. We discuss two models: A
fully harmonic system, and a model incorporating anharmonic interactions. For
both models the control reservoirs induce thermal fluctuations of the
transition elements between molecular vibrational states. We find that a fully
harmonic model does not show any controllability, while for an anharmonic
system the conduction properties of the junction strongly depend on the
parameters of the gates. Realizations of the model system within nanodevices
and macromolecules are discussed.
