A proposal for realizing a 3-qubit controlled-phase gate with superconducting qubit systems coupled to a cavity

Abstract

We present a way to realize a 3-qubit quantum controlled-phase gate with superconducting qubit systems coupled to a cavity. This proposal does not require adjustment of the qubit level spacings or identical qubit-cavity coupling constants. Moreover, since only a resonant interaction is applied, the gate can be performed fast, within $\sim $ 10 nanosecond. This proposal is quite general, which can be applied to various types of superconducting qubits, atoms trapped in a cavity, or quantum dots coupled to a resonator.

9 pages, 5 figures, accepted by Progress of Theoretical Physics. arXiv admin note: substantial text overlap with arXiv:1207.7065, arXiv:1207.6768