Controllable entanglement preparations between atoms in spatially-separated cavities via quantum Zeno dynamics

Abstract

By using quantum Zeno dynamics, we propose a controllable approach to deterministically generate tripartite GHZ states for three atoms trapped in spatially separated cavities. The nearest-neighbored cavities are connected via optical fibers and the atoms trapped in two ends are tunably driven. The generation of the GHZ state can be implemented by only one step manipulation, and the EPR entanglement between the atoms in two ends can be further realized deterministically by Von Neumann measurement on the middle atom. Note that the duration of the quantum Zeno dynamics is controllable by switching on/off the applied external classical drivings and the desirable tripartite GHZ state will no longer evolve once it is generated. The robustness of the proposal is numerically demonstrated by considering various decoherence factors, including atomic spontaneous emissions, cavity decays and fiber photon leakages, etc. Our proposal can be directly generalized to generate multipartite entanglement by still driving the atoms in two ends.

One-step deterministic generation ofN-atom Greenberger–Horne–Zeilinger states in separate coupled cavities via quantum Zeno dynamics

“…Generally speaking, entanglement of multi-qubit shows more nonclassical effects and is more useful for quantum applications [3,4]. Therefore, multi-qubit entanglement states have occupied an important place in modern quantum research because of their promising prospect in quantum information processing, such as quantum computing [5,6], quantum cryptography [7], quantum teleportation [8,9], quantum secret sharing [10], and so on [11][12][13][14][15].…”

“…It is worthy to note that the cavity quantum electrodynamics (C-QED) system, which concerns the interaction of atoms and photons within cavities [22], attracts much attention and is deemed to another ideal candidate for quantum entangled states engineering. Based on C-QED system, many schemes [4,16,17,[23][24][25][26][27][28][29] have been proposed to generate multi-qubit GHZ states with trapped atoms. For example, Deng et al [23] have proposed an interesting scheme for preparation of atomic GHZ states with the help of controlled phaseflip gates [30].…”

“…For example, Deng et al [23] have proposed an interesting scheme for preparation of atomic GHZ states with the help of controlled phaseflip gates [30]. Li et al [4] have proposed a scheme to generate atom GHZ states with the resonant condition via quantum Zeno dynamics (QZD). Hao et al [24] have also presented an efficient scheme to generate GHZ states via adiabatic passage.…”

“…Hao et al [24] have also presented an efficient scheme to generate GHZ states via adiabatic passage. But both their schemes [4,24] have a common drawback: they coupled singlet modal cavity with bimodal-modal (left-circularly polarized cavity mode and right-circularly polarized cavity mode) cavity via a singlet modal optical fiber because such a scheme is difficult to be realized under the modern experimental condition. What is more, the scheme in Ref.…”

Implementation of a Remote Three-Qubit Controlled-Z Gate via Quantum Zeno Dynamics

“…This evolution is called quantum Zeno dynamics (QZD) [18]. Recently, a number of interesting schemes [21][22][23][24][25][26][27][28][29][30] which are based on QZD have been proposed to generate quantum entanglement and to realize quantum logic gates. However, only the implementation of two-qubit controlled phase gate for two six-level atoms separately trapped in two cavities coupled by an optical fiber was discussed [30].…”