Multichannel resonant tunneling of a diatomic molecule

I present the resonance structures of transitions between bound states of a diatomic molecule which is incident upon a potential barrier. Multichannel resonant tunneling is studied by applying repeated feedback substitution to a formal coupled-channel solution formulated by using the Green's function method in one-dimensional model. The characteristics of the resonances are investigated by obtaining the probabilities of transmission and reflection in multichannel resonant tunneling. In the multichannel formalism, the associated reflection amplitude is shown to be symmetric for a symmetric potential. In the numerical results, the probability of tunneling appears to decrease with the opening, or the increasing, of upward transitions, but increases with the opening of downward transitions. The resonances of transmission in multichannel tunneling are found to be very sharp for a strong barrier and are, therefore, applicable to a quantum filter.