Quantum Interference and Complex Photon Statistics in Waveguide QED

TL;DR

This paper investigates photon statistics in waveguide QED systems with one or two qubits, revealing how quantum interference influences photon bunching, antibunching, and complex correlations through a quantum jump approach.

Contribution

It introduces a quantum jump method tailored for waveguide QED, providing new insights into photon statistics and correlations, including complex behaviors hidden in traditional measures.

Findings

Photon bunching is linked to quantum jumps increasing qubit population.

Waiting time distributions offer clearer characterization of photon correlations.

Complex photon correlations can be identified beyond $g^{(2)}( au)$ analysis.

Abstract

We obtain photon statistics by using a quantum jump approach tailored to a system in which one or two qubits are coupled to a one-dimensional waveguide. Photons confined in the waveguide have strong interference effects, which are shown to play a vital role in quantum jumps and photon statistics. For a single qubit, for instance, bunching of transmitted photons is heralded by a jump that increases the qubit population. We show that the distribution and correlations of waiting times offer a clearer and more precise characterization of photon bunching and antibunching. Further, the waiting times can be used to characterize complex correlations of photons which are hidden in $g^{(2)}(\tau)$, such as a mixture of bunching and antibunching.