Quantum statistics and self-interference in extended colliders

TL;DR

This paper investigates extended quantum colliders, revealing how self-interference can mimic fermionic bunching and proposing a current correlator to accurately determine particle statistics.

Contribution

It introduces a model for extended fermionic and bosonic colliders, analyzing self-interference effects and proposing a method to measure true quantum statistics.

Findings

Self-interference causes apparent fermionic bunching in extended colliders.

A specific current correlator can distinguish true fermionic statistics from interference effects.

Extended colliders exhibit multiple trajectories, affecting particle correlation measurements.

Abstract

Collision of quantum particles remains an effective way of probing their mutual statistics. Colliders based on quantum point contacts in quantum Hall edge states have been successfully used to probe the statistics of the underlying quantum particles. Notwithstanding the extensive theoretical work focusing on point-like colliders, when it comes to experiment, the colliders are rarely point-like objects and can support a resonant level or multiple tunneling points. We present a study of a paradigmatic extended (non-point-like) fermionic collider (and an extension to bosonic colliders). As with particle interferometers, in an extended collider there is an infinite number of trajectories for any single or multi-particle event. Self-interference of the former can lead to an apparent bunching of fermions when we compare the cross-current correlator with a classical benchmark representing two colliding beams. In view of this apparent bunching behavior of fermions, we identify an experimentally accessible current correlator which reveals the true mutual statistics of fermions.