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Title: Preparation of entangled states of four remote atomic qubits in decoherence-free subspace

Abstract

We propose how to prepare four remote logical qubits, with each in a separate cavity and encoded in the decoherence-free subspace by two atoms, into various entangled states. By means of the cavity-assisted photon scattering, we can link the four remote logical qubits in different cavities to be, respectively, W state, Greenberger-Horne-Zeilinger state, and cluster state, which are important in view of the distributed quantum information processing. The generation of the latter two entangled states can be theoretically generalized to many-qubit cases. Because our qubits are defined in dephasing-free subspace, our scheme is immune to dephasing during or even after the entanglement preparation.

Authors:
 [1];  [2]; ;  [1]
  1. State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China)
  2. (China)
Publication Date:
OSTI Identifier:
20982197
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.75.024302; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; INFORMATION THEORY; PHOTON-ATOM COLLISIONS; PHOTONS; QUANTUM COMPUTERS; QUANTUM DECOHERENCE; QUANTUM ENTANGLEMENT; QUANTUM MECHANICS; QUBITS

Citation Formats

Deng, Z. J., Graduate School of the Chinese Academy of Sciences, Beijing 100049, Feng, M., and Gao, K. L.. Preparation of entangled states of four remote atomic qubits in decoherence-free subspace. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.024302.
Deng, Z. J., Graduate School of the Chinese Academy of Sciences, Beijing 100049, Feng, M., & Gao, K. L.. Preparation of entangled states of four remote atomic qubits in decoherence-free subspace. United States. doi:10.1103/PHYSREVA.75.024302.
Deng, Z. J., Graduate School of the Chinese Academy of Sciences, Beijing 100049, Feng, M., and Gao, K. L.. Thu . "Preparation of entangled states of four remote atomic qubits in decoherence-free subspace". United States. doi:10.1103/PHYSREVA.75.024302.
@article{osti_20982197,
title = {Preparation of entangled states of four remote atomic qubits in decoherence-free subspace},
author = {Deng, Z. J. and Graduate School of the Chinese Academy of Sciences, Beijing 100049 and Feng, M. and Gao, K. L.},
abstractNote = {We propose how to prepare four remote logical qubits, with each in a separate cavity and encoded in the decoherence-free subspace by two atoms, into various entangled states. By means of the cavity-assisted photon scattering, we can link the four remote logical qubits in different cavities to be, respectively, W state, Greenberger-Horne-Zeilinger state, and cluster state, which are important in view of the distributed quantum information processing. The generation of the latter two entangled states can be theoretically generalized to many-qubit cases. Because our qubits are defined in dephasing-free subspace, our scheme is immune to dephasing during or even after the entanglement preparation.},
doi = {10.1103/PHYSREVA.75.024302},
journal = {Physical Review. A},
number = 2,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
  • Known quantum pure states of a qudit can be remotely prepared onto a group of particles of qubits exactly or probabilistically with the aid of two-level Einstein-Podolsky-Rosen states. We present a protocol for such kind of remote state preparation. We are mainly focused on the remote preparation of the ensembles of equatorial states and those of states in real Hilbert space. In particular, a kind of states of qudits in real Hilbert space have been shown to be remotely prepared in faith without the limitation of the input space dimension.
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  • We study the non-Markovian entanglement dynamics of two qubits in a common squeezed bath. We see a remarkable difference between the non-Markovian entanglement dynamics and its Markovian counterpart. We show that a non-Markovian decoherence-free state is also decoherence free in the Markovian regime, but all the Markovian decoherence-free states are not necessarily decoherence free in the non-Markovian domain. We extend our calculation from a squeezed vacuum bath to a squeezed thermal bath, where we see the effect of finite bath temperatures on the entanglement dynamics.
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