The generation of entanglement in mesoscopic atomic ensembles is a challengingtask for the fields of quantum information quantum teleportation and precisionmeas... » 

The generation of entanglement in mesoscopic atomic ensembles is a challengingtask for the fields of quantum information quantum teleportation and precisionmeasurements. A few subsets of such collective entangled states are analyzed inthis work spin squeezed states Schrodinger cat states and Dicke states.Environmental decoherence is also considered as it affects the quality ofentanglement and a simple formalism for treating cooperative decay of coherenceof multilevel atoms is developed and exemplified in a two qubit case. «