Atomic cluster state build up with macroscopic heralding

TL;DR

This paper presents a measurement-based method for efficiently creating large cluster states in atom-cavity systems, using macroscopic heralding signals instead of single-photon detection, achieving high fidelities.

Contribution

It introduces a novel scheme that employs macroscopic fluorescence signals for heralded cluster state generation, avoiding the need for single-photon detection.

Findings

High fidelities achieved near the bad cavity limit

Heralding is based on macroscopic signals, not single photons

Method is robust to system size variations

Abstract

We describe a measurement-based state preparation scheme for the efficient build up of cluster states in atom-cavity systems. As in a recent proposal for the generation of maximally entangled atom pairs [Metz et al., Phys. Rev. Lett. 97, 040503 (2006)], we use an electron shelving technique to avoid the necessity for the detection of single photons. Instead, the successful fusion of smaller into larger clusters is heralded by an easy-to-detect macroscopic fluorescence signal. High fidelities are achieved even in the vicinity of the bad cavity limit and are essentially independent of the concrete size of the system parameters.