Electron interferometer formed with a scanning probe tip and quantum point contact

TL;DR

This paper demonstrates an electron interferometer using a quantum point contact and a scanning gate tip in a 2D electron gas, revealing interference patterns and effects of dephasing influenced by various parameters.

Contribution

It introduces a novel electron interferometer setup combining a QPC and SGM tip, analyzing how different factors affect interference in a 2D electron system.

Findings

Interference patterns depend on the distance between QPC and SGM tip.

Temperature and electron energy influence dephasing effects.

Conductance varies with cavity length and reflectivity.

Abstract

We show an electron interferometer between a quantum point contact (QPC) and a scanning gate microscope (SGM) tip in a two-dimensional electron gas. The QPC and SGM tip act as reflective barriers of a lossy cavity; the conductance through the system thus varies as a function of the distance between the QPC and SGM tip. We characterize how temperature, electron wavelength, cavity length, and reflectivity of the QPC barrier affect the interferometer. We report checkerboard interference patterns near the QPC and, when injecting electrons above or below the Fermi energy, effects of dephasing.