Disorder-induced enhancement of the quantum size effects in quantum wires with a tunnel barrier

In this paper, we report results of a theoretical study that demonstrates an unexpected effect of disorder on the conductance of quantum wires. It is known that disorder suppresses quantum size effects arising from the lateral confinements in the structure of the conductance. The presence of a tunnel barrier in ballistic wires also destroys the quantum size effects. However, in wires with a weak barrier, introduction of disorder can recover the suppressed quantum size effects. We present a qualitative explanation for this interesting result. © 1996 The American Physical Society.