Entanglement of single-atom quantum bits at a distance (original) (raw)
- Letter
- Published: 06 September 2007
- P. Maunz1,
- S. Olmschenk1,
- K. C. Younge1,
- D. N. Matsukevich1,
- L.-M. Duan1 &
- …
- C. Monroe1,2
Nature volume 449, pages 68–71 (2007)Cite this article
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Abstract
Quantum information science involves the storage, manipulation and communication of information encoded in quantum systems, where the phenomena of superposition and entanglement can provide enhancements over what is possible classically1,2. Large-scale quantum information processors require stable and addressable quantum memories, usually in the form of fixed quantum bits (qubits), and a means of transferring and entangling the quantum information between memories that may be separated by macroscopic or even geographic distances. Atomic systems are excellent quantum memories, because appropriate internal electronic states can coherently store qubits over very long timescales. Photons, on the other hand, are the natural platform for the distribution of quantum information between remote qubits, given their ability to traverse large distances with little perturbation. Recently, there has been considerable progress in coupling small samples of atomic gases through photonic channels2,3, including the entanglement between light and atoms4,5 and the observation of entanglement signatures between remotely located atomic ensembles6,7,8. In contrast to atomic ensembles, single-atom quantum memories allow the implementation of conditional quantum gates through photonic channels2,9, a key requirement for quantum computing. Along these lines, individual atoms have been coupled to photons in cavities2,10,11,12, and trapped atoms have been linked to emitted photons in free space13,14,15,16,17. Here we demonstrate the entanglement of two fixed single-atom quantum memories separated by one metre. Two remotely located trapped atomic ions each emit a single photon, and the interference and detection of these photons signals the entanglement of the atomic qubits. We characterize the entangled pair by directly measuring qubit correlations with near-perfect detection efficiency. Although this entanglement method is probabilistic, it is still in principle useful for subsequent quantum operations and scalable quantum information applications18,19,20.
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References
- Nielsen, M. A. & Chuang, I. L. Quantum Computation and Quantum Information (Cambridge Univ. Press, Cambridge, UK, 2000)
MATH Google Scholar - Zoller, P. et al. Quantum information processing and communication. Eur. Phys. J. D 36, 203–228 (2005)
Article ADS CAS Google Scholar - Duan, L.-M., Lukin, M. D., Cirac, J. I. & Zoller, P. Long-distance quantum communication with atomic ensembles and linear optics. Nature 414, 413–418 (2001)
Article ADS CAS Google Scholar - Sherson, J., Julsgaard, B. & Polzik, E. S. Deterministic atom-light quantum interface. Adv. At. Mol. Opt. Phys. 54, 82–130 (2006)
ADS Google Scholar - Jenkins, S. D. et al. Quantum telecommunication with atomic ensembles. J. Opt. Soc. Am. B 24, 316–323 (2007)
Article ADS CAS Google Scholar - Julsgaard, B., Kozhekin, A. & Polzik, E. S. Experimental long-lived entanglement of two macroscopic objects. Nature 413, 400–403 (2001)
Article ADS CAS Google Scholar - Chou, C. W. et al. Measurement-induced entanglement for excitation stored in remote atomic ensembles. Nature 438, 828–832 (2005)
Article ADS CAS Google Scholar - Matsukevich, D. N. et al. Entanglement of remote atomic qubits. Phys. Rev. Lett. 96, 030405 (2006)
Article ADS CAS Google Scholar - Duan, L.-M. et al. Probabilistic quantum gates between remote atoms through interference of optical frequency qubits. Phys. Rev. A. 76, 062324 (2006)
Article ADS Google Scholar - Berman, P. (ed.) Cavity Quantum Electrodynamics (Academic Press, San Diego, California, 1994)
Google Scholar - McKeever, J. et al. Deterministic generation of single photons from one atom trapped in a cavity. Science 303, 1992–1994 (2004)
Article ADS CAS Google Scholar - Wilk, T., Webster, S. C., Kuhn, A. & Rempe, G. Single-Atom Single-Photon Quantum Interface. Science 317, 488–490 (2007)
Article ADS CAS Google Scholar - Blinov, B. B., Moehring, D. L., Duan, L.-M. & Monroe, C. Observation of entanglement between a single trapped atom and a single photon. Nature 428, 153–157 (2004)
Article ADS CAS Google Scholar - Moehring, D. L., Madsen, M. J., Blinov, B. B. & Monroe, C. Experimental bell inequality violation with an atom and a photon. Phys. Rev. Lett. 93, 090410 (2004)
Article ADS CAS Google Scholar - Beugnon, J. et al. Quantum interference between two single photons emitted by independently trapped atoms. Nature 440, 779–782 (2006)
Article ADS CAS Google Scholar - Volz, J. et al. Observation of entanglement of a single photon with a trapped atom. Phys. Rev. Lett. 96, 030404 (2006)
Article ADS Google Scholar - Moehring, D. L. et al. Quantum networking with photons and trapped atoms. J. Opt. Soc. Am. B 24, 300–315 (2007)
Article ADS CAS Google Scholar - Duan, L.-M., Blinov, B. B., Moehring, D. L. & Monroe, C. Scaling trapped ions for quantum computation with probabilistic ion-photon mapping. Quant. Inf. Comp. 4, 165–173 (2004)
CAS MATH Google Scholar - Duan, L.-M. & Raussendorf, R. Efficient quantum computation with probabilistic quantum gates. Phys. Rev. Lett. 95, 080503 (2005)
Article ADS MathSciNet Google Scholar - Barrett, S. D. & Kok, P. Efficient high-fidelity quantum computation using matter qubits and linear optics. Phys. Rev. A 71, 060310(R) (2005)
Article ADS Google Scholar - Olmschenk, S. et al. Manipulation and detection of a trapped Yb+ ion hyperfine qubit. Preprint at 〈http://arxiv.org/abs/0708.0657〉 (2007)
- Berkeland, D. J. & Boshier, M. G. Destabilization of dark states and optical spectroscopy in Zeeman-degenerate atomic systems. Phys. Rev. A. 65, 033413 (2002)
Article ADS Google Scholar - Maunz, P., Moehring, D. L., Olmschenk, S., Younge, K. C., Matsukevich, D. N. & Monroe, C. Quantum interference of photon pairs from two remote trapped atomic ions. Nature Phys. 3, 538–541 (2007)
Article ADS CAS Google Scholar - Dehmelt, H. Radiofrequency spectroscopy of stored ions. I: Storage. Adv. At. Mol. Phys. 3, 53–72 (1967)
Article ADS CAS Google Scholar - Hong, C. K., Ou, Z. Y. & Mandel, L. Measurement of subpicosecond time intervals between two photons by interference. Phys. Rev. Lett. 59, 2044–2046 (1987)
Article ADS CAS Google Scholar - Simon, C. & Irvine, W. T. M. Robust long-distance entanglement and a loophole-free Bell test with ions and photons. Phys. Rev. Lett. 91, 110405 (2003)
Article ADS Google Scholar - Legero, T., Wilk, T., Kuhn, A. & Rempe, G. Characterization of single photons using two-photon interference. Adv. At. Mol. Opt. Phys. 53, 253–289 (2006)
Article ADS CAS Google Scholar - Bollinger, J. J., Heinzen, D. J., Itano, W. M., Gilbert, S. L. & Wineland, D. J. A 303 MHz Frequency Standard based on Trapped Be+ Ions. IEEE Trans. Inst. Meas. 40, 126–128 (1991)
Article CAS Google Scholar - Roos, C. F. et al. Bell states of atoms with ultralong lifetimes and their tomographic state analysis. Phys. Rev. Lett. 92, 220402 (2004)
Article ADS CAS Google Scholar - Langer, C. et al. Long-lived qubit memory using atomic ions. Phys. Rev. Lett. 95, 060502 (2005)
Article ADS CAS Google Scholar - Madsen, M. J. et al. Ultrafast coherent excitation of a trapped ion qubit for fast gates and photon frequency qubits. Phys. Rev. Lett. 97, 040505 (2006)
Article ADS CAS Google Scholar - Bennett, C. H., DiVincenzo, D. P., Smolin, J. A. & Wootters, W. K. Mixed-state entanglement and quantum error correction. Phys. Rev. A 54, 3824–3851 (1996)
Article ADS MathSciNet CAS Google Scholar - Hill, S. & Wootters, W. K. Entanglement of a pair of quantum bits. Phys. Rev. Lett. 78, 5022–5025 (1997)
Article ADS CAS Google Scholar
Acknowledgements
This work is supported by the National Security Agency and the Disruptive Technology Office under Army Research Office contract, and the National Science Foundation Information Technology Research (ITR) and Physics at the Information Frontier (PIF) programmes.
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Authors and Affiliations
- FOCUS Center and Department of Physics, University of Michigan, Ann Arbor, Michigan 48109-1040, USA,
D. L. Moehring, P. Maunz, S. Olmschenk, K. C. Younge, D. N. Matsukevich, L.-M. Duan & C. Monroe - JQI and Department of Physics, University of Maryland, College Park, Maryland 20742, USA,
C. Monroe
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Correspondence toD. L. Moehring.
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Moehring, D., Maunz, P., Olmschenk, S. et al. Entanglement of single-atom quantum bits at a distance.Nature 449, 68–71 (2007). https://doi.org/10.1038/nature06118
- Received: 17 May 2007
- Accepted: 14 July 2007
- Issue Date: 06 September 2007
- DOI: https://doi.org/10.1038/nature06118
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