Quantum phase gate through the dispersive atom–field interaction with atoms trapped in optical cavity QED

• A experimental feasible scheme for implementing two-qubit quantum phase gate.
• Based on the dispersive interaction between the optical cavity mode and the symmetrically configurated three-level atoms.
• Influence of the cavity decay on the gate fidelity is discussed.

We propose an experimental feasible scheme for implementing two-qubit quantum phase gate with atoms trapped in an optical cavity. The scheme is based on the dispersive interaction between the optical cavity mode and the three-level atoms in Λ configuration, which has been demonstrated in recent cavity-induced spin squeezing experiment (Leroux et al., 2010) [26]. We also discuss the influence of the cavity decay on the gate fidelity. It is shown that the fidelity of the phase gate is robust to the cavity decay and the high-fidelity quantum phase gate can be implemented with the current experimental technology.