Dwell-time distributions in quantum mechanics

TL;DR

This paper reviews the fundamental aspects of quantum dwell time, explores its connection to flux correlations, and discusses quantum-specific features and measurement approaches for dwell time in quantum systems.

Contribution

It provides a comprehensive review of quantum dwell time, including formal definitions, examples, and the relationship to flux-flux correlations, highlighting quantum-specific properties.

Findings

Quantum dwell time differs from classical predictions.

Flux-flux correlations relate to dwell time moments.

Quantum dwell time's second moment exceeds classical values.

Abstract

Some fundamental and formal aspects of the quantum dwell time are reviewed, examples for free motion and scattering off a potential barrier are provided, as well as extensions of the concept. We also examine the connection between the dwell time of a quantum particle in a region of space and flux-flux correlations at the boundaries, as well as operational approaches and approximations to measure the flux-flux correlation function and thus the second moment of the dwell time, which is shown to be characteristically quantum, and larger than the corresponding classical moment even for freely moving particles.