Oscillatory Bohm trajectories in resonant tunneling structures

Tunneling of electrons in double-barrier resonant tunneling diodes (DBRTDs) is studied within the Bohm's formulation of quantum mechanics. As previously done by other authors, stationary scattering states and time-dependent wavepackets are considered. The scattering eigenstates are shown to provide unphysical results, but this is attributed to their actual nature rather than to the failure of Bohm's interpretation. Using time-dependent wavepackets, the behavior of Bohm trajectories at the resonances of DBRTDs is thoroughly examined. The oscillating nature of the resonant trajectories is discussed in terms of the wavefunction energy spectrum and the local density of states in the barrier region. The energy-time uncertainty relationship is shown to provide a necessary condition for the observation of the oscillations which reproduce the intuitive picture of resonances. The case of oscillating trajectories in single potential barriers is also considered as a test of generality. Copyright © 1996 Published by Elsevier Science Ltd.