摘要We propose an effective method to produce four-qubit χ-type entangled states by using flux qubits coupled to an LC circuit which acts as a quantum data bus (QDB). In our scheme, the interaction is mediated by the exchange of virtual rather than real photons because of the large detuning between flux qubits and QDB, and then QDB-induced loss can be effectively avoided. The experimental feasibility of the scheme is also presented.
Abstract：We propose an effective method to produce four-qubit χ-type entangled states by using flux qubits coupled to an LC circuit which acts as a quantum data bus (QDB). In our scheme, the interaction is mediated by the exchange of virtual rather than real photons because of the large detuning between flux qubits and QDB, and then QDB-induced loss can be effectively avoided. The experimental feasibility of the scheme is also presented.
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2012, Vol. 29 
