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:1111.0826 · Physical Review A

Quantum entanglement in nanocavity arrays

T. C. H. Liew, Vincenzo Savona

Published May 7, 2012• 31 citations
arXivHTMLPDF

Abstract

We show theoretically how quantum interference between linearly coupled modes with weak local nonlinearity allows the generation of continuous variable entanglement. By solving the quantum master equation for the density matrix, we show how the entanglement survives realistic levels of pure dephasing. The generation mechanism forms a paradigm for entanglement generation in arrays of coupled quantum modes.

DOI
10.1103/physreva.85.050301

Related papers

Multimode entanglement in coupled cavity arrays

T. C. H. Liew, V Savona

We study a driven-dissipative array of coupled nonlinear optical resonators by numerically solving the von Neumann equation for the density matrix. We demonstrate that quantum correlated states of many photons can also be generated in the limit where the nonlinearity is much smaller than the losses, contrary to common expectations. Quantum correlations in this case arise from the interference between different pathways that the system can follow in the Hilbert space to reach its steady state under the effect of coherent driving fields. We characterize, in particular, two systems: a linear chain of three coupled cavities and an array of eight coupled cavities. We demonstrate the existence of a parameter range where the system emits photons with continuous-variable bipartite and quadripartite entanglement, in the case of the first and the second system, respectively. This entanglement is shown to survive realistic rates of pure dephasing and opens up a new perspective for the realization of quantum simulators or entangled photon sources without the challenging requirement of strong optical nonlinearities.

arXiv:1209.1543•New Journal of Physics•Feb 7, 2013•41 citations

Multimode entanglement in coupled cavity arrays

T. C. H. Liew, Vincenzo Savona

We study a driven-dissipative array of coupled nonlinear optical resonators by numerically solving the von Neumann equation for the density matrix. We demonstrate that quantum correlated states of many photons can also be generated in the limit where the nonlinearity is much smaller than the losses, contrary to common expectations. Quantum correlations in this case arise from the interference between different pathways that the system can follow in the Hilbert space to reach its steady state under the effect of coherent driving fields. We characterize, in particular, two systems: a linear chain of three coupled cavities and an array of eight coupled cavities. We demonstrate the existence of a parameter range where the system emits photons with continuous-variable bipartite and quadripartite entanglement, in the case of the first and the second system, respectively. This entanglement is shown to survive realistic rates of pure dephasing and opens up a new perspective for the realization of quantum simulators or entangled photon sources without the challenging requirement of strong optical nonlinearities.

•Aug 17, 2016•21 citations

Quantum Correlated Photons in Arrays of Weakly Nonlinear Cavities

Vincenzo Savona, T. C. H. Liew

We show, by solving the system’s quantum master equations, that multipartite entangled states of photons can arise in arrays of weakly nonlinear cavities from the interplay of small nonlinear energy shifts and quantum interference between different excitation pathways.

Frontiers in Optics•Jan 1, 2012•0 citations

Entangling two distant nanocavities via a waveguide

Hua-Tang Tan, Wei-Min Zhang, Gao-xiang Li

In this paper, we present a scheme for generating continuous-variable entanglement between two spatially separated nanocavities in photonic crystals, which are mediated by a coupled-resonator optical waveguide. The entanglement degree and purity of the generated states are investigated as varying the cavity frequencies, the cavity-waveguide coupling strength, and the location of the second cavity. It is shown that a steady and pure entanglement between separated nanocavities can be generated only with a weak cavity-waveguide coupling when the cavities are resonant with the band center of the waveguide. Various cases with different cavity frequencies and coupling strengths, which affect the degree of entanglement, are also investigated, and interestingly sudden death and sudden birth of entanglement occur for strong couplings.

arXiv:1103.4021•Physical Review A•Jun 8, 2011•41 citations

Quantum state engineering in arrays of nonlinear waveguides

David Barral, Mattia Walschaers, Kamel Bencheikh +4 more

In the current quest for efficient and experimentally feasible platforms for implementation of multimode squeezing and entanglement in the continuous variable regime, we underpin and complement our results on the generation of versatile multimode entanglement and cluster states in nonlinear waveguide arrays presented by Barral et al., arXiv:1912.11154 [Phys. Rev. Appl. (to be published)]. We present detailed derivations of the equations that describe the propagation of light through this system, and then we focus on parameter regimes where these equations can be solved analytically. These analytical solutions build an intuition for the wide landscape of quantum states that are accessible through the activation of pumping, coupling, and measurement schemes. Furthermore, we showcase the acquired insights by using one of the identified analytical solutions to exhibit the generation, optimization, and scalability of spatial linear cluster states.

arXiv:2005.07240•Physical Review A•Oct 13, 2020•23 citations

Zero supermode-based multipartite entanglement in χ(2) nonlinear waveguide arrays

David Barral, Kamel Bencheikh, Nadia Belabas +1 more

We show that arrays of ${\ensuremath{\chi}}^{(2)}$ nonlinear waveguides in the second-harmonic generation regime are a promising source of continuous-variable entanglement. We indeed demonstrate analytically that optical arrays with an odd number of waveguides injected with the zero-eigenvalue fundamental supermode entangle this fundamental supermode with a collective harmonic field. Moreover, the fundamental individual modes are multipartite entangled and their entanglement grows with propagation length. The device is scalable, robust to losses, does not rely on specific values of nonlinearity and coupling, and is easily realized with current technology. It thus stands as an unprecedented candidate for generation of multipartite continuous-variable entanglement for optical quantum information processing.

arXiv:1903.10074•Physical Review A•May 7, 2019•11 citations
We show theoretically how quantum interference between linearly coupled modes with weak local nonlinearity allows the generation of continuous variable entanglement. By solving the quantum master equation for the density matrix, we show how the entanglement survives realistic levels of pure dephasing. The generation mechanism forms a paradigm for entanglement generation in arrays of coupled quantum modes.
We study a driven-dissipative array of coupled nonlinear optical resonators by numerically solving the von Neumann equation for the density matrix. We demonstrate that quantum correlated states of many photons can also be generated in the limit where the nonlinearity is much smaller than the losses, contrary to common expectations. Quantum correlations in this case arise from the interference between different pathways that the system can follow in the Hilbert space to reach its steady state under the effect of coherent driving fields. We characterize, in particular, two systems: a linear chain of three coupled cavities and an array of eight coupled cavities. We demonstrate the existence of a parameter range where the system emits photons with continuous-variable bipartite and quadripartite entanglement, in the case of the first and the second system, respectively. This entanglement is shown to survive realistic rates of pure dephasing and opens up a new perspective for the realization of quantum simulators or entangled photon sources without the challenging requirement of strong optical nonlinearities.
We study a driven-dissipative array of coupled nonlinear optical resonators by numerically solving the von Neumann equation for the density matrix. We demonstrate that quantum correlated states of many photons can also be generated in the limit where the nonlinearity is much smaller than the losses, contrary to common expectations. Quantum correlations in this case arise from the interference between different pathways that the system can follow in the Hilbert space to reach its steady state under the effect of coherent driving fields. We characterize, in particular, two systems: a linear chain of three coupled cavities and an array of eight coupled cavities. We demonstrate the existence of a parameter range where the system emits photons with continuous-variable bipartite and quadripartite entanglement, in the case of the first and the second system, respectively. This entanglement is shown to survive realistic rates of pure dephasing and opens up a new perspective for the realization of quantum simulators or entangled photon sources without the challenging requirement of strong optical nonlinearities.
In this paper, we present a scheme for generating continuous-variable entanglement between two spatially separated nanocavities in photonic crystals, which are mediated by a coupled-resonator optical waveguide. The entanglement degree and purity of the generated states are investigated as varying the cavity frequencies, the cavity-waveguide coupling strength, and the location of the second cavity. It is shown that a steady and pure entanglement between separated nanocavities can be generated only with a weak cavity-waveguide coupling when the cavities are resonant with the band center of the waveguide. Various cases with different cavity frequencies and coupling strengths, which affect the degree of entanglement, are also investigated, and interestingly sudden death and sudden birth of entanglement occur for strong couplings.
In the current quest for efficient and experimentally feasible platforms for implementation of multimode squeezing and entanglement in the continuous variable regime, we underpin and complement our results on the generation of versatile multimode entanglement and cluster states in nonlinear waveguide arrays presented by Barral et al., arXiv:1912.11154 [Phys. Rev. Appl. (to be published)]. We present detailed derivations of the equations that describe the propagation of light through this system, and then we focus on parameter regimes where these equations can be solved analytically. These analytical solutions build an intuition for the wide landscape of quantum states that are accessible through the activation of pumping, coupling, and measurement schemes. Furthermore, we showcase the acquired insights by using one of the identified analytical solutions to exhibit the generation, optimization, and scalability of spatial linear cluster states.
We show that arrays of ${\ensuremath{\chi}}^{(2)}$ nonlinear waveguides in the second-harmonic generation regime are a promising source of continuous-variable entanglement. We indeed demonstrate analytically that optical arrays with an odd number of waveguides injected with the zero-eigenvalue fundamental supermode entangle this fundamental supermode with a collective harmonic field. Moreover, the fundamental individual modes are multipartite entangled and their entanglement grows with propagation length. The device is scalable, robust to losses, does not rely on specific values of nonlinearity and coupling, and is easily realized with current technology. It thus stands as an unprecedented candidate for generation of multipartite continuous-variable entanglement for optical quantum information processing.