MICROWAVE-INDUCED RESONANT REFLECTION AND LOCALIZATION OF BALLISTIC ELECTRONS IN QUANTUM MICROCHANNELS

TL;DR

This paper demonstrates that microwave electromagnetic fields can induce resonant reflection and localization of ballistic electrons in quantum microchannels, significantly affecting conductance through coherent electron-photon interactions.

Contribution

It introduces a novel mechanism of electron localization in microchannels via microwave-induced resonant reflection involving multiple scattering centers.

Findings

Conductance exhibits irregular dips due to resonant reflection.

Average conductance decays exponentially with channel length.

Microwave fields can fully block electron transport in microchannels.

Abstract

We show that electron transport in a ballistic microchannel supporting both propagating and reflected modes can be completely blocked by applying a microwave electromagnetic field. The effect is due to resonant reflection caused by multiple coherent electron-photon scattering involving at least two spatially localized scattering centers in the channel. With many such scattering centers present the conductance is shown to have an irregular dependence on bias voltage, gate voltage and frequency with irregularily spaced dips corresponding to resonant reflection. When averaged over bias, gate voltage or frequency the conductance will decay exponentially with channel length in full analogy with the localization of 1D electrons caused by impurity scattering.