Deterministic generation of symmetric multi-qubit Dicke states: an application of quantum feedback control

In this study, the authors explore how to deterministically generate symmetric multi-qubit Dicke states such as symmetric W-states, from arbitrary initial states in a cavity quantum electrodynamics (QED) system with the aid of measurement-based quantum feedback control. The concrete implementation procedures of the feedback strategy, which is constructed in the form of only two constant modes, are presented in detail. In addition, the feasibility of the control scheme in preparing symmetric multi-qubit Dicke states is explicitly demonstrated by theoretical studies and numerical simulations.