Influence of statistics on decoherence and quantum Zeno dynamics

Anu Venugopalan, Rupamanjari Ghosh

Zhi‐Cheng Shi, Yan Xia, Jie Song +1 more

In this paper, we first demonstrate how to realize quantum state transferring (QST) from one atom to another based on quantum Zeno dynamics. Then, the QST protocol is generalized to realize the quantum state swapping (QSS) between two arbitrary atoms with the help of a third one. Furthermore, we also consider the QSS within a quantum network. The influence of decoherence is analyzed by numerical calculation. The results demonstrate that the protocols are robust against cavity decay.

Michael B. Mensky

Ying‐Li Liu, Wen‐Xue Cui, Shou Zhang +1 more

ABSTRACT Bell state and W state are not just common entangled states, they are foundational resources in the field of quantum information. In this scheme, a Rydberg atomic ensemble with a four‐level “”‐shaped structure is confined within a Rydberg blockade sphere to form a superatom. Exploiting the unique advantages of the weak cavity field limit, the quantum information can be encoded with reliability on the superatom's effective energy levels. By integrating the methods of quantum Zeno dynamics (QZD) and Lewis‐Riesenfeld (LR) invariants, the Bell state, three‐qubit W state, and ‐qubit W state are prepared rapidly. Furthermore, the influences exerted by decoherence factors are also factored in. Numerical simulations confirm that the present scheme not only achieves high fidelities but also exhibits robustness against these decoherence factors. Finally, we further investigate the influences of parameter fluctuations on fidelities, and the results demonstrate that the fidelities of the proposed scheme remain robust against parameter fluctuations.

Rupamanjari Ghosh, Anu Venugopalan

Wenan Li, Guang-Yao Huang

A scheme is proposed for the generation of a three-dimensional entangled state for two atoms trapped in a cavity via quantum Zeno dynamics. Because the scheme is based on the resonant interaction, the time required to produce entanglement is very short compared with the dispersive protocols. We show that the resulting effective dynamics allows for the creation of robust qutrit-qutrit entanglement. The influence of various decoherence processes such as spontaneous emission and photon loss on the fidelity of the entangled state is investigated. Numerical results show that the scheme is robust against the cavity decay since the evolution of the system is restricted to a subspace with null-excitation cavity fields. Furthermore, the present scheme has been generalized to realize $N$-dimensional entanglement for two atoms.