Shortcuts to adiabatic for implementing controlled phase gate with Cooper-pair box qubits in circuit quantum electrodynamics system

Abstract

We theoretically present a protocol to realize the controlled phase gate with Cooper-pair box (CPB) qubits in circuit quantum electrodynamics (circuit QED) system. In this protocol, the one-dimensional transmission line resonator in circuit QED system acting as quantum data bus generates a common cavity mode and interacts with each CPB qubit. The Rabi frequencies of driven pluses can be designed with simple Gaussian or trigonometric functions by utilizing the universal SU(2) transformation. Moreover, the level configurations of CPB qubits have been reported by previous protocol (Feng and Zhang in Phys C 470:240–243, 2010). Thus, the protocol can be realized easily in experiment. In addition, the influence of various decoherence processes such as spontaneous emissions, dephasings of the CPB qubits and the decay of the cavity mode on the fidelity is discussed by numerical simulations. The results show that the protocol is robust against the decoherence and parameter variations. Therefore, the protocol may be useful for the fields of quantum computations.