OSCILLATORY BOHM TRAJECTORIES IN RESONANT-TUNNELING STRUCTURES

Tunneling of electrons in double-barrier resonant tunneling diodes (DB RTDs) is studied within the Bohm's formulation of quantum mechanics. A s previously done by other authors, stationary scattering states and t ime-dependent wavepackets are considered. The scattering eigenstates a re shown to provide unphysical results, but this is attributed to thei r actual nature rather than to the failure of Bohm's interpretation. U sing time-dependent wavepackets, the behavior of Bohm trajectories at the resonances of DBRTDs is thoroughly examined. The oscillating natur e of the resonant trajectories is discussed in terms of the wavefuncti on energy spectrum and the local density of states in the barrier regi on. The energy-time uncertainty relationship is shown to provide a nec essary condition for the observation of the oscillations which reprodu ce the intuitive picture of resonances. The case of oscillating trajec tories in single potential barriers is also considered as a test of ge nerality. Copyright (C) 1996 Published by Elsevier Science Ltd.