Imaging Electron Interferometer

TL;DR

This paper reports the development of an imaging electron interferometer in a 2D electron gas, demonstrating interference fringes, a quantum phase shifter, and an interferometric spectrometer, with robustness against thermal effects.

Contribution

It introduces a novel imaging electron interferometer using a circular mirror and quantum point contact, enabling new electron wave manipulation techniques.

Findings

Interference fringes observed with a scanning probe microscope.

A quantum phase shifter created by gate-controlled mirror movement.

Interferometric spectrometer demonstrated by sweeping the tip over wavelengths.

Abstract

An imaging interferometer was created in a two-dimensional electron gas by reflecting electron waves emitted from a quantum point contact (QPC) with a circular mirror. Images of electron flow obtained with a scanning probe microscope at liquid He temperatures show interference fringes when the mirror is energized. A quantum phase shifter was created by moving the mirror via its gate voltage, and an interferometric spectrometer can be formed by sweeping the tip over many wavelengths. Experiments and theory demonstrate that the interference signal is robust against thermal averaging.