A Mesoscopic Quantum Eraser

TL;DR

This paper proposes a mesoscopic quantum eraser using an Aharonov-Bohm interferometer with a quantum dot and a finite-state detector, demonstrating how interference can be restored through specific measurements on the detector.

Contribution

It introduces a novel mesoscopic quantum eraser concept based on a two-particle scattering approach and measurement strategies to recover quantum interference.

Findings

Interference is reduced due to dephasing from the detector.

Proper measurement on the detector can restore the interference.

The approach is applicable to mesoscopic quantum systems.

Abstract

Motivated by a recent experiment by Buks et al. [Nature 391, 871 (1998)] we consider electron transport through an Aharonov-Bohm interferometer with a quantum dot in one of its arms. The quantum dot is coupled to a quantum system with a finite number of states acting as a which-path detector. The Aharonov-Bohm interference is calculated using a two-particle scattering approach for the joint transitions in detector and quantum dot. Tracing over the detector yields dephasing and a reduction of the interference amplitude. We show that the interference can be restored by a suitable measurement on the detector and propose a mesoscopic quantum eraser based on this principle.