Analyzing quantum jumps of one and two atoms strongly coupled to an optical cavity

TL;DR

This paper demonstrates nondestructive measurement of atomic spin states in strongly coupled atom-cavity systems by analyzing quantum jumps and photon signals, employing Bayesian methods to optimize information extraction.

Contribution

It introduces a method to infer atomic hyperfine states nondestructively using photon streams and Bayesian analysis in a strongly coupled atom-cavity setup.

Findings

Achieved nondestructive spin state detection with high fidelity.

Developed a Bayesian framework for real-time state probability updates.

Analyzed effects of atomic motion on photon statistics.

Abstract

We induce quantum jumps between the hyperfine ground states of one and two Cesium atoms, strongly coupled to the mode of a high-finesse optical resonator, and analyze the resulting random telegraph signals. We identify experimental parameters to deduce the atomic spin state nondestructively from the stream of photons transmitted through the cavity, achieving a compromise between a good signal-to-noise ratio and minimal measurement-induced perturbations. In order to extract optimum information about the spin dynamics from the photon count signal, a Bayesian update formalism is employed, which yields time-dependent probabilities for the atoms to be in either hyperfine state. We discuss the effect of super-Poissonian photon number distributions caused by atomic motion.