We present an efficient way for measuring the entanglement of the atoms. Through the auxiliary single photons input-output process in cavity quantum electrodynamics (QED), the concurrence of the atomic entanglement can be obtained according to the success probability of picking up the singlet states of the atoms. This protocol has three advantages: First, we do not require the sophisticated controlled-not (CNOT) gates. Second, the distributed atoms are not required to intact with each other. Third, the atomic entanglement can be distributed nonlocally, which provides its important applications in distributed quantum computation.We present an efficient way for measuring the entanglement of the atoms. Through the auxiliary single photons input-output process in cavity quantum electrodynamics (QED), the concurrence of the atomic entanglement can be obtained according to the success probability of picking up the singlet states of the atoms. This protocol has three advantages: First, we do not require the sophisticated controlled-not (CNOT) gates. Second, the distributed atoms are not required to intact with each other. Third, the atomic entanglement can be distributed nonlocally, which provides its important applications in distributed quantum computation.

arXiv:1401.2526Jan 11, 20140 citations

Quantum controlled-not gate in the bad cavity regime

Zhao-Hui Peng, Le‐Man Kuang, Jian Zou +2 more

Quantum Information ProcessingMay 13, 20158 citations

Nonlocal d-dimensional Controlled-NOT with Multi-target Gate: AControlled and Local Implementation

Libing Chen, Yihong Bai, Haiping Lu

Journal of the Korean Physical SocietyMar 14, 20111 citation

Quantum gating on neutral atoms in low- Q cavities by a single-photon input-output process

Qiong Chen, Mang Feng

We investigate the possibility to achieve quantum gates using atoms confined in low- $Q$ cavities by single-photon input-output process. Different from in high- $Q$ cavities with strong coupling, we may accomplish universal quantum gates on the atoms by Faraday rotations. Our idea could be applied to multiqubit gating on local and nonlocal atoms as well as on encoded qubits in decoherence-free subspace.We investigate the possibility to achieve quantum gates using atoms confined in low-$Q$ cavities by single-photon input-output process. Different from in high-$Q$ cavities with strong coupling, we may accomplish universal quantum gates on the atoms by Faraday rotations. Our idea could be applied to multiqubit gating on local and nonlocal atoms as well as on encoded qubits in decoherence-free subspace.

Physical Review AJun 15, 200954 citations

One-Way Flagged Probabilistic Implementation of a Nonlocal Controlled-NOT Gate

Xiaonan Zhang, Yu-Guang Yang, Guang-Bao Xu +1 more

Brazilian Journal of PhysicsOct 5, 20260 citations

Scalable quantum computation via a coherent state input–output process in a low-Qcavity in the atom–cavity intermediate coupling region

Cong Cao, Chuan Xi Wang, Tie-Jun Wang +1 more

We propose a basic scheme to construct a hybrid controlled phase-flip (CPF) gate between a flying pulse qubit and a stationary atomic qubit, assisted by a cavity input–output process for a low-Q cavity in the atom–cavity intermediate coupling region. The qubits can be encoded on the coherent states and ground states of the single-trapped L-level atom, respectively. We present a theoretical model of the hybrid CPF gate, whose basic strategy is to control the reflectivity of the input coherent optical pulse to obtain a phase shift conditioned by the different internal atomic states by adjusting the parameters of the cavity quantum electrodynamics (CQED) system. The resulting basic scheme can be used to construct nonlocal gates between remote atomic qubits confined in spatially separated cavities, and also for the generation of an atomic cluster state. The performance and experimental feasibilities of the proposed scheme indicate that it is robust against practical noise and feasible with current technologies. Thus, our scheme is applicable for use in large-scale quantum computation.We propose a basic scheme to construct a hybrid controlled phase-flip (CPF) gate between a flying pulse qubit and a stationary atomic qubit, assisted by a cavity input–output process for a low-Q cavity in the atom–cavity intermediate coupling region. The qubits can be encoded on the coherent states and ground states of the single-trapped L-level atom, respectively. We present a theoretical model of the hybrid CPF gate, whose basic strategy is to control the reflectivity of the input coherent optical pulse to obtain a phase shift conditioned by the different internal atomic states by adjusting the parameters of the cavity quantum electrodynamics (CQED) system. The resulting basic scheme can be used to construct nonlocal gates between remote atomic qubits confined in spatially separated cavities, and also for the generation of an atomic cluster state. The performance and experimental feasibilities of the proposed scheme indicate that it is robust against practical noise and feasible with current technologies. Thus, our scheme is applicable for use in large-scale quantum computation.

Laser PhysicsNov 1, 20133 citations

We investigate the possibility to achieve quantum gates using atoms confined in low-

Q

cavities by single-photon input-output process. Different from in high-

Q

cavities with strong coupling, we may accomplish universal quantum gates on the atoms by Faraday rotations. Our idea could be applied to multiqubit gating on local and nonlocal atoms as well as on encoded qubits in decoherence-free subspace.