Parameter estimation by multi-channel photon counting

TL;DR

This paper develops a theoretical framework for estimating physical parameters of quantum light sources using multi-channel photon counting, analyzing waiting time distributions to optimize sensitivity in complex emission processes.

Contribution

It introduces a new theory for parameter estimation from photon counting data, including branching emission processes with distinguishable photons, and applies it to a laser-driven $$-type atom.

Findings

Provides formulas for asymptotic sensitivity limits

Applies theory to a $$-type atomic system

Enhances understanding of quantum parameter estimation

Abstract

The physical parameters governing the dynamics of a light emitting quantum system can be estimated from the photon counting signal. The information available in the full detection record can be analysed by means of the distribution of waiting times between detection events. Our theory allows calculation of the asymptotic, long time behaviour of the sensitivity limit, and it applies to emission processes with branching towards different final states accompanied by the emission of distinguishable photons. We illustrate the theory by application to a laser driven $\Lambda$-type atom.