Heralded Entanglement between Atomic Ensembles: Preparation, Decoherence, and Scaling

TL;DR

This paper demonstrates heralded entanglement between atomic ensembles, analyzing its generation, decay, and scalability, with quantitative measures and insights into the dynamics affecting entanglement longevity.

Contribution

It introduces a probabilistic method for creating and characterizing entanglement in atomic ensembles, including a lower bound on concurrence and analysis of entanglement decay over time.

Findings

Concurrence lower bound of 0.9±0.3 for atomic entanglement.

Entanglement decay observed and related to local dynamics.

Scalability behavior of entanglement with excitation probability analyzed.

Abstract

Heralded entanglement between collective excitations in two atomic ensembles is probabilistically generated, stored, and converted to single photon fields. By way of the concurrence, quantitative characterizations are reported for the scaling behavior of entanglement with excitation probability and for the temporal dynamics of various correlations resulting in the decay of entanglement. A lower bound of the concurrence for the collective atomic state of 0.9\pm 0.3 is inferred. The decay of entanglement as a function of storage time is also observed, and related to the local dynamics.