Quantum interference in the time-of-flight distribution

TL;DR

This paper proposes an experimental scheme to observe matter-wave interference in the time-of-flight distribution of atomic BEC Schrödinger-cat states, highlighting quantum coherence effects in the time domain.

Contribution

It introduces a novel method to detect quantum interference in the TOF distribution using the quantum probability current density, contrasting with classical approaches.

Findings

Quantum interference in TOF distribution predicted and quantified.

Interference disappears for large atomic masses.

Potential to test different theoretical models of quantum arrival times.

Abstract

We propose a scheme to experimentally observe matter-wave interference in the time domain, specifically in the arrival-time or the time-of-flight (TOF) distribution for atomic BEC Schrodinger-cat state represented by superposition of macroscopically separated wave packets in space. This is in contrast to interference in space at a fixed time observed in reported BEC experiments. We predict and quantify the quantum interference in the TOF distribution calculated from the modulus of the quantum probability current density (rather than the TOF distributions obtained from a purely classical or semi-classical treatment in many reported experiments). The interference and hence the coherence in the quantum TOF signal disappears in the large-mass limit. Our scheme has the potential to probe the validity of various other theoretical approaches (Phys. Rep. 338, 353 (2000)) of calculating the quantum arrival time distribution.