Abstract
We have studied the propagation of guided electron waves in two coupled quantum wells. Coupled quantum wells with single-well multimodes are analyzed by decomposing the one-dimensional coupled eigenstates in terms of the multiple eigenstates of the individual wells. The energy transfer from a particular mode in a channel to all the other modes either in the same channel or in the other channel along the propagating direction are characterized. The dominant transfer is to the same mode in the other channel. Apart from minor features due to the presence of the other modes, the tunneling is approximately the same as the shallow-well single-mode case for the coupled pair. But tunneling to other modes nearest in energy to the incident mode in both channels is found to be quite large, particularly under high-mode injection. For low electron energies the transfer between the two dominant modes in the two channels is incomplete; this is found to be associated with mixed modes that occur at the input end of the waveguide.
- Received 18 July 1991
DOI:https://doi.org/10.1103/PhysRevB.44.13618
©1991 American Physical Society