Conditional preparation of arbitrary atomic Dicke states

TL;DR

This paper introduces a practical method for conditionally creating highly non-classical collective spin states in atomic ensembles using quantum nondemolition interactions, non-Gaussian light states, and measurement-based state engineering.

Contribution

It presents a novel, experimentally feasible protocol for non-deterministically preparing superpositions of atomic Dicke states with optimized fidelity and success probability.

Findings

Protocol enables non-classical state preparation in atomic ensembles.

Optimization techniques improve fidelity-success trade-off.

Method is adaptable for various superpositions of Dicke states.

Abstract

We propose an experimentally accessible procedure for conditional preparation of highly non-classical states of collective spin of an atomic ensemble. The quantum state engineering is based on a combination of QND interaction between atoms and light previously prepared in a non-Gaussian state using photon subtraction from squeezed vacuum beam, homodyne detection on the output light beam, and a coherent displacement of atomic state. The procedure is capable of non-deterministic preparation of a wide class of superpositions of atomic Dicke states. We present several techniques to optimize the performance of the protocol and maximize the trade-off between fidelity of prepared state and success probability of the scheme.