Coherent detection of electron dephasing

TL;DR

This paper demonstrates that an Aharonov-Bohm ring with asymmetric electron injection can detect electron dephasing coherently, changing its transmission properties while maintaining electron coherence, effectively functioning as an interaction-free measurement device.

Contribution

It introduces a novel use of an asymmetric AB ring as a coherent, interaction-free detector of electron dephasing, highlighting its potential for quantum measurement applications.

Findings

Dephasing source alters the ring's response from reflection to transmission

Electron coherence is preserved despite strong dephasing

The system functions as an interaction-free measurement device

Abstract

We show that an Aharonov-Bohm (AB) ring with asymmetric electron injection can act as a coherent detector of electron dephasing. The presence of a dephasing source in one of the two arms of a moderately-to-highly asymmetric ring changes the response of the system from total reflection to complete transmission while preserving the coherence of the electrons propagating from the ring, even for strong dephasing. We interpret this phenomenon as an implementation of an interaction-free measurement.