Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:0709.2144 · Physical Review A

On-demand generation of entanglement of atomic qubits via optical interferometry

Y. P. Huang, M. G. Moore

Published Mar 31, 2008• 10 citations
arXivHTMLPDF

Abstract

The problem of on-demand generation of entanglement between single-atom qubits via a common photonic channel is examined within the framework of optical interferometry. As expected, for a Mach-Zehnder interferometer with coherent laser beam as input, a high-finesse optical cavity is required to overcome sensitivity to spontaneous emission. We show, however, that with a twin-Fock input, useful entanglement can in principle be created without cavity enhancement. Both approaches require single-photon resolving detectors, and best results would be obtained by combining both cavity feedback and twin-Fock inputs. Such an approach may allow a fidelity of 0.99 using a two-photon input and currently available mirror and detector technology. In addition, we study interferometers based on NOON states, i.e., maximally entangled $N$-particle states, and show that they perform similarly to the twin-Fock states, yet without the need for high-precision photodetectors. The present interferometrical approach can serve as a universal, scalable circuit element for quantum information processing, from which fast quantum gates, deterministic teleportation, entanglement swapping, etc., can be realized with the aid of single-qubit operations.

DOI
10.1103/physreva.77.032349

Related papers

Long-distance teleportation of atomic qubit via optical interferometry

Y. P. Huang, M. G. Moore

The problem of long-distance teleportation of single-atom qubits via a common photonic channel is examined within the framework of a Mach-Zender optical interferometer. As expected, when a coherent state is used as input, a high-finesse optical cavity is required to overcome sensitivity to spontaneous emission. However, we find that a number-squeezed light field in a twin-Fock state can in principle create useful entanglement without cavity-enhancement. Both approaches require single photon counting detectors, and best results are obtained by combining cavity-feedback with twin-fock inputs. Such an approach may allow a fidelity of $.99$ using a two-photon input and currently available mirror and detector technology. In addition, the present approach can be conveniently extended to generate multi-site entanglement and entanglement swapping, both of which are necessities in quantum networks.

arXiv:quant-ph/0609214•Sep 27, 2006•0 citations

Generation of atom-light entanglement in an optical cavity for quantum enhanced atom interferometry

Simon A. Haine, W. Y. Sarah Lau

We theoretically investigate the generation of atom-light entanglement via Raman superradiance in an optical cavity, and show how this can be used to enhance the sensitivity of atom interferometry. We model a realistic optical cavity, and show that by careful temporal shaping of the optical local oscillator used to measure the light emitted from the cavity, information in the optical mode can be combined with the signal from the atom interferometer to reduce the quantum noise, and thus increase the sensitivity. It was found in Phys. Rev. Lett. 110, 053002 (2013) that an atomic ``seed'' was required in order to reduce spontaneous emission and allow for single mode behavior of the device. In this paper we find that the optical cavity reduces the need for an atomic seed, which allows for stronger atom-light correlations and a greater level of quantum enhancement.

arXiv:1511.03050•Physical Review A•Feb 3, 2016•21 citations

Generation of hybrid entanglement between a single-photon polarization qubit and a coherent state

Hyukjoon Kwon, Hyunseok Jeong

We propose a scheme to generate entanglement between a single-photon qubit in the polarization basis and a coherent state of light. The required resources are a superposition of coherent states, a polarization entangled photon pair, beam splitters, the displacement operation, and four photodetectors. Even when realistic detectors with a limited efficiency are used, an arbitrarily high fidelity can be obtained by adjusting a beam-splitter ratio and the displacement amplitude at the price of reducing the success probability. Our analysis shows that high fidelities may be obtained using on-off detectors with low efficiencies and available resource states under current technology.

arXiv:1410.6823•Physical Review A•Jan 29, 2015•43 citations

Engineering maximally entangledN-photon NOON field states using an atom interferometer based on Bragg regime cavity QED

Rameez‐ul‐Islam, Manzoor Ikram, Farhan Saif

We propose a scheme for generation of highly non-classical entangled field states of the type in the cavity QED scenario. The scheme utilizes an atomic analogue of the Mach–Zehnder interferometer having a quantized field in the high- Q cavity containing a superposition of zero and one photon that acts as the first beam splitter. The probability for production of the desired states may approach a value close to unity with high fidelity under prevailing experimental conditions.

Journal of Physics B Atomic Molecular and Optical Physics•Mar 9, 2007•44 citations

Interaction- and measurement-free quantum Zeno gates for universal computation with single-atom and single-photon qubits

Y. P. Huang, M. G. Moore

By extending the concept of interaction-free imaging to the few-atom level, we show that asymptotically on-demand interaction- and measurement-free quantum logic gates can be realized for both single-atom and single-photon qubits. The interaction-free feature suppresses the possibility of qubit decoherence via atomic spontaneous decay, while the elimination of measurements can significantly reduce errors arising from detector inefficiency. We present a general theory of universal quantum Zeno gates, and discuss physical implementations for quantum-information processing with individual atoms and photons. In addition, we propose a loss-tolerant protocol for long-distance quantum communication using quantum Zeno gates incorporated into a Mach-Zehnder interferometer. The efficiency of our Zeno gates is limited primarily by the imprecise control of atom-photon scattering and the finite number of feedback cycles $N$ due to the limited finesse of the optical ring cavity. We find that the success probability scales as $1\ensuremath{-}O(1/N)$, and for realistic parameters could be as high as 98.4%. Successful generation of atom-atom entanglement can be heralded by detection of the ancillary photon, upon which the fidelity scales as $1\ensuremath{-}O(1/{N}^{2})$, with an achievable fidelity of 99.994%, which comes at the cost of reducing the success probability by the detector efficiency.

Physical Review A•Jun 19, 2008•44 citations

Efficient generation of entangled multiphoton graph states from a single atom

Philip Thomas, Leonardo Ruscio, Olivier Morin +1 more

Abstract The central technological appeal of quantum science resides in exploiting quantum effects, such as entanglement, for a variety of applications, including computing, communication and sensing 1 . The overarching challenge in these fields is to address, control and protect systems of many qubits against decoherence 2 . Against this backdrop, optical photons, naturally robust and easy to manipulate, represent ideal qubit carriers. However, the most successful technique so far for creating photonic entanglement 3 is inherently probabilistic and, therefore, subject to severe scalability limitations. Here we report the implementation of a deterministic protocol 4–6 for the creation of photonic entanglement with a single memory atom in a cavity 7 . We interleave controlled single-photon emissions with tailored atomic qubit rotations to efficiently grow Greenberger–Horne–Zeilinger (GHZ) states 8 of up to 14 photons and linear cluster states 9 of up to 12 photons with a fidelity lower bounded by 76(6)% and 56(4)%, respectively. Thanks to a source-to-detection efficiency of 43.18(7)% per photon, we measure these large states about once every minute, which is orders of magnitude faster than in any previous experiment 3,10–13 . In the future, this rate could be increased even further, the scheme could be extended to two atoms in a cavity 14,15 or several sources could be quantum mechanically coupled 16 , to generate higher-dimensional cluster states 17 . Overcoming the limitations encountered by probabilistic schemes for photonic entanglement generation, our results may offer a way towards scalable measurement-based quantum computation 18,19 and communication 20,21 .

arXiv:2205.12736•Nature•Aug 24, 2022•208 citations
The problem of on-demand generation of entanglement between single-atom qubits via a common photonic channel is examined within the framework of optical interferometry. As expected, for a Mach-Zehnder interferometer with coherent laser beam as input, a high-finesse optical cavity is required to overcome sensitivity to spontaneous emission. We show, however, that with a twin-Fock input, useful entanglement can in principle be created without cavity enhancement. Both approaches require single-photon resolving detectors, and best results would be obtained by combining both cavity feedback and twin-Fock inputs. Such an approach may allow a fidelity of 0.99 using a two-photon input and currently available mirror and detector technology. In addition, we study interferometers based on NOON states, i.e., maximally entangled NNN-particle states, and show that they perform similarly to the twin-Fock states, yet without the need for high-precision photodetectors. The present interferometrical approach can serve as a universal, scalable circuit element for quantum information processing, from which fast quantum gates, deterministic teleportation, entanglement swapping, etc., can be realized with the aid of single-qubit operations.
The problem of long-distance teleportation of single-atom qubits via a common photonic channel is examined within the framework of a Mach-Zender optical interferometer. As expected, when a coherent state is used as input, a high-finesse optical cavity is required to overcome sensitivity to spontaneous emission. However, we find that a number-squeezed light field in a twin-Fock state can in principle create useful entanglement without cavity-enhancement. Both approaches require single photon counting detectors, and best results are obtained by combining cavity-feedback with twin-fock inputs. Such an approach may allow a fidelity of .99.99.99 using a two-photon input and currently available mirror and detector technology. In addition, the present approach can be conveniently extended to generate multi-site entanglement and entanglement swapping, both of which are necessities in quantum networks.
We theoretically investigate the generation of atom-light entanglement via Raman superradiance in an optical cavity, and show how this can be used to enhance the sensitivity of atom interferometry. We model a realistic optical cavity, and show that by careful temporal shaping of the optical local oscillator used to measure the light emitted from the cavity, information in the optical mode can be combined with the signal from the atom interferometer to reduce the quantum noise, and thus increase the sensitivity. It was found in Phys. Rev. Lett. 110, 053002 (2013) that an atomic ``seed'' was required in order to reduce spontaneous emission and allow for single mode behavior of the device. In this paper we find that the optical cavity reduces the need for an atomic seed, which allows for stronger atom-light correlations and a greater level of quantum enhancement.
We propose a scheme to generate entanglement between a single-photon qubit in the polarization basis and a coherent state of light. The required resources are a superposition of coherent states, a polarization entangled photon pair, beam splitters, the displacement operation, and four photodetectors. Even when realistic detectors with a limited efficiency are used, an arbitrarily high fidelity can be obtained by adjusting a beam-splitter ratio and the displacement amplitude at the price of reducing the success probability. Our analysis shows that high fidelities may be obtained using on-off detectors with low efficiencies and available resource states under current technology.
By extending the concept of interaction-free imaging to the few-atom level, we show that asymptotically on-demand interaction- and measurement-free quantum logic gates can be realized for both single-atom and single-photon qubits. The interaction-free feature suppresses the possibility of qubit decoherence via atomic spontaneous decay, while the elimination of measurements can significantly reduce errors arising from detector inefficiency. We present a general theory of universal quantum Zeno gates, and discuss physical implementations for quantum-information processing with individual atoms and photons. In addition, we propose a loss-tolerant protocol for long-distance quantum communication using quantum Zeno gates incorporated into a Mach-Zehnder interferometer. The efficiency of our Zeno gates is limited primarily by the imprecise control of atom-photon scattering and the finite number of feedback cycles NNN due to the limited finesse of the optical ring cavity. We find that the success probability scales as $1\ensuremath{-}O(1/N)$, and for realistic parameters could be as high as 98.4%. Successful generation of atom-atom entanglement can be heralded by detection of the ancillary photon, upon which the fidelity scales as $1\ensuremath{-}O(1/{N}^{2})$, with an achievable fidelity of 99.994%, which comes at the cost of reducing the success probability by the detector efficiency.
Abstract The central technological appeal of quantum science resides in exploiting quantum effects, such as entanglement, for a variety of applications, including computing, communication and sensing 1 . The overarching challenge in these fields is to address, control and protect systems of many qubits against decoherence 2 . Against this backdrop, optical photons, naturally robust and easy to manipulate, represent ideal qubit carriers. However, the most successful technique so far for creating photonic entanglement 3 is inherently probabilistic and, therefore, subject to severe scalability limitations. Here we report the implementation of a deterministic protocol 4–6 for the creation of photonic entanglement with a single memory atom in a cavity 7 . We interleave controlled single-photon emissions with tailored atomic qubit rotations to efficiently grow Greenberger–Horne–Zeilinger (GHZ) states 8 of up to 14 photons and linear cluster states 9 of up to 12 photons with a fidelity lower bounded by 76(6)% and 56(4)%, respectively. Thanks to a source-to-detection efficiency of 43.18(7)% per photon, we measure these large states about once every minute, which is orders of magnitude faster than in any previous experiment 3,10–13 . In the future, this rate could be increased even further, the scheme could be extended to two atoms in a cavity 14,15 or several sources could be quantum mechanically coupled 16 , to generate higher-dimensional cluster states 17 . Overcoming the limitations encountered by probabilistic schemes for photonic entanglement generation, our results may offer a way towards scalable measurement-based quantum computation 18,19 and communication 20,21 .