Search

Current passing in the forward direction through a GaAs-based heterojunction at liquid helium temperatures exhibits, under a strong magnetic field applied parallel to the junction plane, regular fluctuations. We argue that these fluctuations are associated with the formation of closed Aharonov-Bohm-type orbits encircling misfit dislocations generated at the interface in which the current carriers are temporarily trapped.

Solid-state analogue of the electrostatic Aharonov-Bohn effect has been predicted for a long time. Basing on this effect, hypothetical designs of quantum interference transistor have been proposed but, surprisingly, they have never been realised in practice. We show that this failure is principal due to inherent instability of such devices against charge fluctuations.

Presents experimental results obtained with resonant-tunneling diodes fabricated from (GaAl)As/GaAs and (CdMg)Te/CdTe semiconductor heterostructures grown - respectively - by low-pressure metal-organic vapor-phase epitaxy and molecular-beam epitaxy methods. These results demonstrate, firstly, the appearance of intriguing oscillatory structure on the rising slope of the resonant peak in small-diameter (GaAl)As/GaAs-based devices and, secondly, the improvement of current-voltage characteristics of (CdMg)Te/CdTe-based resonant-tunneling diodes due to reduction of their cross-sectional area.