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:1111.4103 · Physical Review A

Quantum correlations by four-wave mixing in an atomic vapor in a nonamplifying regime: Quantum beam splitter for photons

Quentin C. Glorieux, Luca Guidoni, S. Guibal, J.-P. Likforman, T. Coudreau

Published Nov 14, 2011• 77 citations
arXivHTMLPDF

Abstract

We study the generation of intensity quantum correlations using four-wave mixing in a rubidium vapor. The absence of cavities in these experiments allows to deal with several spatial modes simultaneously. In the standard amplifying configuration, we measure relative intensity squeezing up to 9.2 dB below the standard quantum limit. We also theoretically identify and experimentally demonstrate an original regime where, despite no overall amplification, quantum correlations are generated. In this regime, a four-wave mixing setup can play the role of a photonic beam splitter with nonclassical properties, that is, a device that splits a coherent state input into two quantum-correlated beams.

DOI
10.1103/physreva.84.053826

Related papers

ETUDE THEORIQUE ET EXPERIMENTALE DES CORRELATIONS QUANTIQUES OBTENUES PAR MELANGE A QUATRE ONDES DANS UNE VAPEUR ATOMIQUE

Quentin C. Glorieux

Abstract We study both theoretically and experimentally the generation of quantum correlations in the continuous variable regime by way of four-wave mixing in a hot atomic vapor. Two theoretical approaches have been developed. On one side, we study the four- wave mixing under the "classical" non-linear optics point of view. In such a way we obtain the evolution equation for an ideal linear amplifier in a χ(3) medium. On the other side, we present a microscopic model with 4 levels in the double-Λ configuration to calculate the χ(3) coefficient in a atomic vapor dressed with a laser. This calculation allows us to derive the spectra of intensity noise for interesting parameters. The experimental part of this work describes the demonstration of this effect on the D1 line of rubidium 85. We present a measurement of relative intensity squeezing as high as -9.2dB below the standard quantum limit, and an original regime where quantum correlations have been measured without amplification. These results have broad applications in the field of multimode quantum optics, e.g. quantum imaging or the multimode quantum memories. Keywords quantum fluctuations, squeezing, quantum correlations, atomic vapor, four wave mixing, continuous variable, entanglement.

arXiv:1101.5166•Nov 19, 2010•2 citations

ETUDE THEORIQUE ET EXPERIMENTALE DES CORRELATIONS QUANTIQUES OBTENUES PAR MELANGE A QUATRE ONDES DANS UNE VAPEUR ATOMIQUE

Quentin C. Glorieux

Abstract We study both theoretically and experimentally the generation of quantum correlations in the continuous variable regime by way of four-wave mixing in a hot atomic vapor. Two theoretical approaches have been developed. On one side, we study the four- wave mixing under the "classical" non-linear optics point of view. In such a way we obtain the evolution equation for an ideal linear amplifier in a χ(3) medium. On the other side, we present a microscopic model with 4 levels in the double-Λ configuration to calculate the χ(3) coefficient in a atomic vapor dressed with a laser. This calculation allows us to derive the spectra of intensity noise for interesting parameters. The experimental part of this work describes the demonstration of this effect on the D1 line of rubidium 85. We present a measurement of relative intensity squeezing as high as -9.2dB below the standard quantum limit, and an original regime where quantum correlations have been measured without amplification. These results have broad applications in the field of multimode quantum optics, e.g. quantum imaging or the multimode quantum memories. Keywords quantum fluctuations, squeezing, quantum correlations, atomic vapor, four wave mixing, continuous variable, entanglement.

•Nov 19, 2010•6 citations

Experimental generation of quadruple quantum-correlated beams from hot rubidium vapor by cascaded four-wave mixing using spatial multiplexing

Leiming Cao, Jian Feng Qi, Jinjian Du +1 more

Multimode quantum states, such as multipartite quantum entanglement or quantum correlations, are important for both fundamental science and the future development of quantum technologies. Here we theoretically propose and experimentally realize a scheme that can fully exploit the multi-spatial-mode nature of the four-wave-mixing (FWM) process, i.e., spatial multiplexing, and thus integrates multiple FWM processes into a single cell at each stage of the cascaded process. The number of generated quantum-correlated beams ${2}^{n}$ is exponentially dependent on the number of vapor cells $n$. In addition, the quantum correlations between the multiple beams also increase as the number of vapor cell increases. For the case of $n=2$, we experimentally show that the degree of intensity-difference squeezing between the four quantum-correlated beams in our scheme is enhanced to $\ensuremath{-}8.2\ifmmode\pm\else\textpm\fi{}0.2$ dB from $\ensuremath{-}5.6\ifmmode\pm\else\textpm\fi{}0.3$ and $\ensuremath{-}6.5\ifmmode\pm\else\textpm\fi{}0.2$ dB of squeezing obtained with a single FWM process. Our system may find applications in quantum information and precision measurement.

Physical Review A•Feb 2, 2017•45 citations

Generating quantum correlated twin beams by four-wave mixing in hot cesium vapor

Rong Ma, Wei Liu, Zhongzhong Qin +2 more

Using a nondegenerate four-wave mixing process based on a double-$\mathrm{\ensuremath{\Lambda}}$ scheme in hot cesium vapor, we generate quantum correlated twin beams with a maximum intensity-difference squeezing of 6.5 dB. The substantially improved squeezing can be mainly attributed to very good frequency and phase-difference stability between the pump and probe beams in our experiment. Intensity-difference squeezing can be observed within a wide experimental parameter range, which guarantees its robust generation. Since this scheme produces multi-spatial-mode twin beams at the Cs ${D}_{1}$ line, it is of interest for experiments involving quantum imaging and coherent interfaces between atomic and solid-state systems.

arXiv:1710.06706•Physical Review A•Oct 17, 2017•24 citations

Generation of tripartite squeezed state by cascaded four-wave mixing in single hot rubidium atomic system

Changbiao Li, Yufeng Li, Wei Li +4 more

Abstract We report the quantum correlated triple beams via cascaded four-wave mixing (CFWM) amplified in single hot atomic vapor. Experimentally, we show that strong quantum correlation of three light beams, among them any two’s quantum correlation is characterized by the maximum value of intensity-difference squeezing (IDS) about −7.8 ± 0.3 dB. We found there is IDS between two idler beams, because two pairs of Einstein–Podolsky–Rosen injections potentially exist in our system. Besides, CFWM can emit three-mode beams at three different frequencies, in which these beams can be well separated in the spatial domain. Moreover, much difference with other methods, the injecting probe field can manipulate the gain and IDS of output three-mode light beams, which is resulting from competition relationship between cascaded two four-wave mixing processes. More interestingly, Autler–Townes splitting of gain peaks of output signals due to dressing effect of pumping fields, will lead to the evolution of measured two- and three-mode IDS from single-mode to multi-mode at frequency domain. This result will provide a multimode quantum resource which can potentially realize multimode entanglement and quantum networks.

New Journal of Physics•Aug 30, 2022•11 citations

Experimental Generation of Multiple Quantum Correlated Beams from Hot Rubidium Vapor

Zhongzhong Qin, Leiming Cao, Hailong Wang +3 more

Quantum correlations and entanglement shared among multiple quantum modes are important for both fundamental science and the future development of quantum technologies. This development will also require an efficient quantum interface between multimode quantum light sources and atomic ensembles, which makes it necessary to implement multimode quantum light sources that match the atomic transitions. Here, we report on such a source that provides a method for generating quantum correlated beams that can be extended to a large number of modes by using multiple four-wave mixing (FWM) processes in hot rubidium vapor. Experimentally, we show that two cascaded FWM processes produce strong quantum correlations between three bright beams but not between any two of them. In addition, the intensity-difference squeezing is enhanced with the cascaded system to -7.0±0.1 dB from the -5.5±0.1/-4.5±0.1 dB squeezing obtained with only one FWM process. One of the main advantages of our system is that as the number of quantum modes increases, so does the total degree of quantum correlations. The proposed method is also immune to phase instabilities due to its phase insensitive nature, can easily be extended to multiple modes, and has potential applications in the production of multiple quantum correlated images.

arXiv:1407.3863•Physical Review Letters•Jul 10, 2014•193 citations
We study the generation of intensity quantum correlations using four-wave mixing in a rubidium vapor. The absence of cavities in these experiments allows to deal with several spatial modes simultaneously. In the standard amplifying configuration, we measure relative intensity squeezing up to 9.2 dB below the standard quantum limit. We also theoretically identify and experimentally demonstrate an original regime where, despite no overall amplification, quantum correlations are generated. In this regime, a four-wave mixing setup can play the role of a photonic beam splitter with nonclassical properties, that is, a device that splits a coherent state input into two quantum-correlated beams.
Abstract We study both theoretically and experimentally the generation of quantum correlations in the continuous variable regime by way of four-wave mixing in a hot atomic vapor. Two theoretical approaches have been developed. On one side, we study the four- wave mixing under the "classical" non-linear optics point of view. In such a way we obtain the evolution equation for an ideal linear amplifier in a χ(3) medium. On the other side, we present a microscopic model with 4 levels in the double-Λ configuration to calculate the χ(3) coefficient in a atomic vapor dressed with a laser. This calculation allows us to derive the spectra of intensity noise for interesting parameters. The experimental part of this work describes the demonstration of this effect on the D1 line of rubidium 85. We present a measurement of relative intensity squeezing as high as -9.2dB below the standard quantum limit, and an original regime where quantum correlations have been measured without amplification. These results have broad applications in the field of multimode quantum optics, e.g. quantum imaging or the multimode quantum memories. Keywords quantum fluctuations, squeezing, quantum correlations, atomic vapor, four wave mixing, continuous variable, entanglement.
Abstract We study both theoretically and experimentally the generation of quantum correlations in the continuous variable regime by way of four-wave mixing in a hot atomic vapor. Two theoretical approaches have been developed. On one side, we study the four- wave mixing under the "classical" non-linear optics point of view. In such a way we obtain the evolution equation for an ideal linear amplifier in a χ(3) medium. On the other side, we present a microscopic model with 4 levels in the double-Λ configuration to calculate the χ(3) coefficient in a atomic vapor dressed with a laser. This calculation allows us to derive the spectra of intensity noise for interesting parameters. The experimental part of this work describes the demonstration of this effect on the D1 line of rubidium 85. We present a measurement of relative intensity squeezing as high as -9.2dB below the standard quantum limit, and an original regime where quantum correlations have been measured without amplification. These results have broad applications in the field of multimode quantum optics, e.g. quantum imaging or the multimode quantum memories. Keywords quantum fluctuations, squeezing, quantum correlations, atomic vapor, four wave mixing, continuous variable, entanglement.
Multimode quantum states, such as multipartite quantum entanglement or quantum correlations, are important for both fundamental science and the future development of quantum technologies. Here we theoretically propose and experimentally realize a scheme that can fully exploit the multi-spatial-mode nature of the four-wave-mixing (FWM) process, i.e., spatial multiplexing, and thus integrates multiple FWM processes into a single cell at each stage of the cascaded process. The number of generated quantum-correlated beams 2n{2}^{n}2n is exponentially dependent on the number of vapor cells nnn. In addition, the quantum correlations between the multiple beams also increase as the number of vapor cell increases. For the case of n=2n=2n=2, we experimentally show that the degree of intensity-difference squeezing between the four quantum-correlated beams in our scheme is enhanced to $\ensuremath{-}8.2\ifmmode\pm\else\textpm\fi{}0.2$ dB from $\ensuremath{-}5.6\ifmmode\pm\else\textpm\fi{}0.3$ and $\ensuremath{-}6.5\ifmmode\pm\else\textpm\fi{}0.2$ dB of squeezing obtained with a single FWM process. Our system may find applications in quantum information and precision measurement.
Using a nondegenerate four-wave mixing process based on a double-$\mathrm{\ensuremath{\Lambda}}$ scheme in hot cesium vapor, we generate quantum correlated twin beams with a maximum intensity-difference squeezing of 6.5 dB. The substantially improved squeezing can be mainly attributed to very good frequency and phase-difference stability between the pump and probe beams in our experiment. Intensity-difference squeezing can be observed within a wide experimental parameter range, which guarantees its robust generation. Since this scheme produces multi-spatial-mode twin beams at the Cs D1{D}_{1}D1​ line, it is of interest for experiments involving quantum imaging and coherent interfaces between atomic and solid-state systems.
Abstract We report the quantum correlated triple beams via cascaded four-wave mixing (CFWM) amplified in single hot atomic vapor. Experimentally, we show that strong quantum correlation of three light beams, among them any two’s quantum correlation is characterized by the maximum value of intensity-difference squeezing (IDS) about −7.8 ± 0.3 dB. We found there is IDS between two idler beams, because two pairs of Einstein–Podolsky–Rosen injections potentially exist in our system. Besides, CFWM can emit three-mode beams at three different frequencies, in which these beams can be well separated in the spatial domain. Moreover, much difference with other methods, the injecting probe field can manipulate the gain and IDS of output three-mode light beams, which is resulting from competition relationship between cascaded two four-wave mixing processes. More interestingly, Autler–Townes splitting of gain peaks of output signals due to dressing effect of pumping fields, will lead to the evolution of measured two- and three-mode IDS from single-mode to multi-mode at frequency domain. This result will provide a multimode quantum resource which can potentially realize multimode entanglement and quantum networks.
Quantum correlations and entanglement shared among multiple quantum modes are important for both fundamental science and the future development of quantum technologies. This development will also require an efficient quantum interface between multimode quantum light sources and atomic ensembles, which makes it necessary to implement multimode quantum light sources that match the atomic transitions. Here, we report on such a source that provides a method for generating quantum correlated beams that can be extended to a large number of modes by using multiple four-wave mixing (FWM) processes in hot rubidium vapor. Experimentally, we show that two cascaded FWM processes produce strong quantum correlations between three bright beams but not between any two of them. In addition, the intensity-difference squeezing is enhanced with the cascaded system to -7.0±0.1 dB from the -5.5±0.1/-4.5±0.1 dB squeezing obtained with only one FWM process. One of the main advantages of our system is that as the number of quantum modes increases, so does the total degree of quantum correlations. The proposed method is also immune to phase instabilities due to its phase insensitive nature, can easily be extended to multiple modes, and has potential applications in the production of multiple quantum correlated images.