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

Entanglement rate for Gaussian continuous variable beams

Zhi Jiao Deng, Steven Habraken, Florian Marquardt

Published Jan 1, 2016• 11 citations
OpenAlex

Abstract

We derive a general expression that quantifies the total entanglement production rate in continuous variable systems, where a source emits two entangled Gaussian beams with arbitrary correlators. This expression is especially useful for situations where the source emits an arbitrary frequency spectrum, e.g. when cavities are involved. To exemplify its meaning and potential, we apply it to a four-mode optomechanical setup that enables the simultaneous up- and down-conversion of photons from a drive laser into entangled photon pairs. This setup is efficient in that both the drive and the optomechanical up- and down-conversion can be fully resonant.

Related papers

Entanglement rate for Gaussian continuous variable beams

Zhi Jiao Deng, Steven Habraken, Florian Marquardt

We derive a general expression that quantifies the total entanglement production rate in continuous variable systems, where a source emits two entangled Gaussian beams with arbitrary correlators. This expression is especially useful for situations where the source emits an arbitrary frequency spectrum, e.g. when cavities are involved. To exemplify its meaning and potential, we apply it to a four-mode optomechanical setup that enables the simultaneous up- and down-conversion of photons from a drive laser into entangled photon pairs. This setup is efficient in that both the drive and the optomechanical up- and down-conversion can be fully resonant.

arXiv:1406.7815•New Journal of Physics•Jun 20, 2016•19 citations

An entanglement rate for continuous variables and its application to a resonant optomechanical multimode setup

Zhi Jiao Deng, Steven Habraken, Florian Marquardt

We introduce a general expression that quantifies the entanglement production rate in continuous variable systems in which entanglement depends on frequency. To exemplify its meaning and potential, we apply it to a four-mode optomechanical setup that enables the simultaneous up- and down-conversion of photons from a drive laser into entangled photon pairs. This setup is efficient in that both the drive and the optomechanical up- and down-conversion can be fully resonant.

•Jun 30, 2014•1 citation

Continuous-variable entanglement in a two-mode lossy cavity: An analytic solution

Colin Vendromin, Marc M. Dignam

Continuous-variable (CV) entanglement is a valuable resource in the field of quantum information. One source of CV entanglement is the correlations between the position and momentum of photons in a two-mode squeezed state of light. In this paper, we theoretically study the generation of squeezed states, via spontaneous parametric down conversion, inside a two-mode lossy cavity that is pumped with a classical optical pulse. The dynamics of the density operator in the cavity is modeled using the Lindblad master equation, and we show that the solution to this model is the density operator for a two-mode squeezed thermal state, with a time-dependent squeezing amplitude and average thermal photon number for each mode. We derive an expression for the minimum correlation variance inside the cavity that depends crucially on the difference in the losses between the two modes. We apply our analytic solution to the important example of a microring resonator that is pumped with a Gaussian pulse. The expressions that we derive will help researchers optimize CV entanglement in lossy cavities.

arXiv:2012.01523•Physical Review A•Feb 17, 2021•17 citations

Externally induced continuous variable entanglement in a correlated emission laser

Sintayehu Tesfa

Analysis of the externally induced quantum features of the cavity radiation of the two-photon correlated emission laser is presented. It turns out that the pumping process induces atomic coherence accountable for observing entanglement in the cavity radiation as well as the nonclassical photon number correlation despite the arising vacuum fluctuations. Even though a significant continuous variable entanglement is obtained near threshold in the strong driving limit, increasing the amplitude of the driving radiation more than required for a fixed value of the linear gain coefficient is found to degrade the degree of entanglement. The two-mode squeezing of the superimposed radiation, entanglement of the cavity radiation and mean number of photon pairs increase with the rate at which the atoms are injected into the cavity, but the nonclassical photon number correlation decreases. Moreover, the mean photon number corresponding to the transition from the upper energy level to the intermediate is found to be greater than the transition from the intermediate to the lower. With conceivable practical challenges, it is in principle possible to generate an intense continuous variable entanglement and quantify it via photon count measurements.

Journal of Physics B Atomic Molecular and Optical Physics•Jun 30, 2008•24 citations

Deterministic generation of bright multicolor entanglement from optomechanical systems

Keyu Xia

Entangled continuous variable (CV) Gaussian states with different wavelengths plays a central role in recent CV-based approaches to quantum network, quantum information processing and quantum metrology. Typically, experiments demonstrating CV entanglement exploit the optical parametric frequency down conversion. Due to the probabilistic nature of photon pair generation, the entanglement involving the post-selection of photonic qubits is limited to at most three colors. Here We theoretically present a scheme for the deterministic generation of entanglement among bright multicolor CV Gaussian states from an optomechanical system using existing experimental technologies. In our scheme an optical frequency comb is input into an optomechanical resonator and then the amplified optomechanical coupling makes multipartite entanglement among them. Our scheme overcomes the limitation of usable frequency of entangled CVs in frequency conversion process. It can be extended to generate multipartite entanglement between orthogonal modes with a single frequency or between microwave and optical CVs, or even among a microwave frequency comb. This optomechanical device can be integrated on a chip.

arXiv:1507.07310•Jul 27, 2015•1 citation

Entanglement beating in a cavity optomechanical system under two-field driving

Chang‐Sheng Hu, Zhiqiang Liu, Ye Liu +3 more

An optomechanical cavity driven by a periodically amplitude-modulated laser can generate steady light-mechanical entanglement with time periodicity. Similar results can be alternatively obtained by pumping an especially tuned optical degenerate parametric amplifier (DPA) inside the cavity. While the two laser beams are simultaneously applied, the optomechanical entanglement can exhibit constructive and destructive interference patterns, depending on their cooperative phase, which further gives rise to beating in entanglement dynamics if the two modulation frequencies are slightly different, followed by a beating frequency-dependent dynamical behavior in the energy exchange between light and a mechanical oscillator. The optimal dynamical entanglement goes beyond what is attainable by the scenario with two superimposed cavity drivings, as a result of the specially DPA-modulated quantum dynamics. Moreover, we calculate correlation spectra between the cavity and mechanical modes, and we find correspondence between the light-oscillator entanglement and the correlation spectra under the cooperative effect. The cooperation-enhanced optomechanical entanglement is robust against the thermal temperature, and is potentially useful for continuous variable quantum information processing.

Physical Review A•Mar 10, 2020•37 citations
We derive a general expression that quantifies the total entanglement production rate in continuous variable systems, where a source emits two entangled Gaussian beams with arbitrary correlators. This expression is especially useful for situations where the source emits an arbitrary frequency spectrum, e.g. when cavities are involved. To exemplify its meaning and potential, we apply it to a four-mode optomechanical setup that enables the simultaneous up- and down-conversion of photons from a drive laser into entangled photon pairs. This setup is efficient in that both the drive and the optomechanical up- and down-conversion can be fully resonant.
We derive a general expression that quantifies the total entanglement production rate in continuous variable systems, where a source emits two entangled Gaussian beams with arbitrary correlators. This expression is especially useful for situations where the source emits an arbitrary frequency spectrum, e.g. when cavities are involved. To exemplify its meaning and potential, we apply it to a four-mode optomechanical setup that enables the simultaneous up- and down-conversion of photons from a drive laser into entangled photon pairs. This setup is efficient in that both the drive and the optomechanical up- and down-conversion can be fully resonant.
Continuous-variable (CV) entanglement is a valuable resource in the field of quantum information. One source of CV entanglement is the correlations between the position and momentum of photons in a two-mode squeezed state of light. In this paper, we theoretically study the generation of squeezed states, via spontaneous parametric down conversion, inside a two-mode lossy cavity that is pumped with a classical optical pulse. The dynamics of the density operator in the cavity is modeled using the Lindblad master equation, and we show that the solution to this model is the density operator for a two-mode squeezed thermal state, with a time-dependent squeezing amplitude and average thermal photon number for each mode. We derive an expression for the minimum correlation variance inside the cavity that depends crucially on the difference in the losses between the two modes. We apply our analytic solution to the important example of a microring resonator that is pumped with a Gaussian pulse. The expressions that we derive will help researchers optimize CV entanglement in lossy cavities.
Analysis of the externally induced quantum features of the cavity radiation of the two-photon correlated emission laser is presented. It turns out that the pumping process induces atomic coherence accountable for observing entanglement in the cavity radiation as well as the nonclassical photon number correlation despite the arising vacuum fluctuations. Even though a significant continuous variable entanglement is obtained near threshold in the strong driving limit, increasing the amplitude of the driving radiation more than required for a fixed value of the linear gain coefficient is found to degrade the degree of entanglement. The two-mode squeezing of the superimposed radiation, entanglement of the cavity radiation and mean number of photon pairs increase with the rate at which the atoms are injected into the cavity, but the nonclassical photon number correlation decreases. Moreover, the mean photon number corresponding to the transition from the upper energy level to the intermediate is found to be greater than the transition from the intermediate to the lower. With conceivable practical challenges, it is in principle possible to generate an intense continuous variable entanglement and quantify it via photon count measurements.
Entangled continuous variable (CV) Gaussian states with different wavelengths plays a central role in recent CV-based approaches to quantum network, quantum information processing and quantum metrology. Typically, experiments demonstrating CV entanglement exploit the optical parametric frequency down conversion. Due to the probabilistic nature of photon pair generation, the entanglement involving the post-selection of photonic qubits is limited to at most three colors. Here We theoretically present a scheme for the deterministic generation of entanglement among bright multicolor CV Gaussian states from an optomechanical system using existing experimental technologies. In our scheme an optical frequency comb is input into an optomechanical resonator and then the amplified optomechanical coupling makes multipartite entanglement among them. Our scheme overcomes the limitation of usable frequency of entangled CVs in frequency conversion process. It can be extended to generate multipartite entanglement between orthogonal modes with a single frequency or between microwave and optical CVs, or even among a microwave frequency comb. This optomechanical device can be integrated on a chip.
An optomechanical cavity driven by a periodically amplitude-modulated laser can generate steady light-mechanical entanglement with time periodicity. Similar results can be alternatively obtained by pumping an especially tuned optical degenerate parametric amplifier (DPA) inside the cavity. While the two laser beams are simultaneously applied, the optomechanical entanglement can exhibit constructive and destructive interference patterns, depending on their cooperative phase, which further gives rise to beating in entanglement dynamics if the two modulation frequencies are slightly different, followed by a beating frequency-dependent dynamical behavior in the energy exchange between light and a mechanical oscillator. The optimal dynamical entanglement goes beyond what is attainable by the scenario with two superimposed cavity drivings, as a result of the specially DPA-modulated quantum dynamics. Moreover, we calculate correlation spectra between the cavity and mechanical modes, and we find correspondence between the light-oscillator entanglement and the correlation spectra under the cooperative effect. The cooperation-enhanced optomechanical entanglement is robust against the thermal temperature, and is potentially useful for continuous variable quantum information processing.