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

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Playing the quantum harp: multipartite squeezing and entanglement of harmonic oscillators

Olivier Pfister, Nicolas C. Menicucci, Steven T. Flammia, Hussain Zaidi, Russell Bloomer, Matthew Pysher

Published Jan 22, 2008• 0 citations
Publisher

Abstract

The frequency comb of an optical resonator is a naturally large set of exquisitely well defined quantum systems, such as in the broadband mode-locked lasers which have redefined time/frequency metrology and ultraprecise measurements in recent years. High coherence can therefore be expected in the quantum version of the frequency comb, in which nonlinear interactions couple different cavity modes, as can be modeled by different forms of graph states. We show that is possible to thereby generate states of interest to quantum metrology and computing, such as multipartite entangled cluster and Greenberger-Horne-Zeilinger states.

DOI
10.1117/12.762995

Related papers

Entangling the optical frequency comb: Simultaneous generation of multiple 2 × 2 and 2 × 3 continuous-variable cluster states in a single optical parametric oscillator

Hussain Zaidi, Nicolas C. Menicucci, Steven T. Flammia +3 more

We report on our research effort to generate large-scale multipartite optical-mode entanglement using as few physical resources as possible. We have previously shown that cluster-and GHZ-type N-partite continuous-variable entanglement can be obtained in an optical resonator that contains a suitably designed second-order nonlinear optical medium, pumped by at most $$ \mathcal{O} $$ (N 2) fields. In this paper, we show that the frequency comb of such a resonator can be entangled in an arbitrary number of independent 2 × 2 and 2 × 3 continuousvariable cluster states by a single optical parametric oscillator pumped by just a few optical modes.

arXiv:0710.4980•Laser Physics•May 1, 2008•38 citations

Graph states and carrier-envelope phase squeezing

Olivier Pfister

We outline a new class of continuous-variable graph states that can be useful to describe entangle- ment, and also multimode squeezing, in an optical frequency comb. We show that a particular case of such states coincides with the squeezing of the carrier-envelope phase, or of the total intensity, of a mode-locked laser. We then discuss the experimental issues related to measuring the quantum noise of the carrier-envelope phase of a frequency comb and show that this can be carried out by use of quantum heterodyne multiplexing, a technique that may be useful to measure multipartite entanglement as well.

arXiv:quant-ph/0701104•Jan 16, 2007•4 citations

Long-range entanglement and quantum correlations in a multi-frequency comb system

Sahil Pontula, Debasmita Banerjee, Marin Soljacic +1 more

Frequency combs are multimode photonic systems that underlie countless precision sensing and metrology applications. Since their invention over two decades ago, numerous efforts have pushed frequency combs to broader bandwidths and more stable operation. More recently, quantum squeezing and entanglement have been explored in single frequency comb systems for quantum advantages in sensing and signal multiplexing. However, the production of quantum light across multiple frequency combs remains unexplored. In this work, we theoretically explore a mechanism that generates a series of nonlinearly coupled frequency combs through cascaded three-wave upconversion and downconversion processes mediated by a single idler comb. We show how this system generates inter- and intracomb two-mode squeezing and entanglement spanning a very large spectral range, from ultraviolet to mid-IR frequencies. Finally, we show how this system can be engineered to produce on-demand multimode quantum light through covariance matrix optimization. Our findings could enable tunable broadband ghost spectroscopy protocols, squeezing-enhanced pump-probe measurements, and broadband entanglement between spectrally-multiplexed quanta of information.

quant-pharXiv:2511.13604•Nov 18, 2025•0 citations

Experimental Generation of a Multipartite Entangled Graph State in the Quantum Optical Frequency Comb

Chun-Hung Chang, Xuan Zhu, Olivier Pfister

We report on experimental progress toward the generation of large-scale multipartite entanglement by phase modulation of an optical parametric oscillator. The graph state will be reconstructed from the covariance matrix built by two-mode measurements.

OSA Quantum 2.0 Conference•Jan 1, 2020•0 citations

Large-scale multipartite entanglement in the quantum optical frequency comb

Reihaneh Shahrokhshahi, Olivier Pfister

We show theoretically that multipartite entanglement is generated on a massive scale in the spectrum, or optical frequency comb, of a single optical parametric oscillator (OPO) emitting well above threshold. In this system, the quantum dynamics of the strongly depleted pump field are responsible for the onset of the entanglement by correlating the two-mode squeezed, bipartite-entangled pairs of OPO signal fields. (Such pairs are independent of one another in the undepleted, classical pump approximation.) We verify the multipartite nature of the entanglement by evaluating the van Loock-Furusawa criterion for a particular set of entanglement witnesses deduced from physical considerations.

Quantum Information and Computation•Nov 1, 2012•1 citation

Multimode squeezing of frequency combs

Germán J. de Valcárcel, Giuseppe Patera, Nicolas Treps +1 more

We have developed a full multimode theory of a synchronously pumped type-I optical parametric oscillator. We calculate the output quantum fluctuations of the device and find that, in the degenerate case (coincident signal and idler set of frequencies), significant squeezing is obtained when one approaches threshold from below for a set of well-defined ``supermodes,'' or frequency combs, consisting of a coherent linear superposition of signal modes of different frequencies which are resonant in the cavity.

Physical Review A•Dec 8, 2006•90 citations
The frequency comb of an optical resonator is a naturally large set of exquisitely well defined quantum systems, such as in the broadband mode-locked lasers which have redefined time/frequency metrology and ultraprecise measurements in recent years. High coherence can therefore be expected in the quantum version of the frequency comb, in which nonlinear interactions couple different cavity modes, as can be modeled by different forms of graph states. We show that is possible to thereby generate states of interest to quantum metrology and computing, such as multipartite entangled cluster and Greenberger-Horne-Zeilinger states.
We report on our research effort to generate large-scale multipartite optical-mode entanglement using as few physical resources as possible. We have previously shown that cluster-and GHZ-type N-partite continuous-variable entanglement can be obtained in an optical resonator that contains a suitably designed second-order nonlinear optical medium, pumped by at most O \mathcal{O} O (N 2) fields. In this paper, we show that the frequency comb of such a resonator can be entangled in an arbitrary number of independent 2 × 2 and 2 × 3 continuousvariable cluster states by a single optical parametric oscillator pumped by just a few optical modes.
We outline a new class of continuous-variable graph states that can be useful to describe entangle- ment, and also multimode squeezing, in an optical frequency comb. We show that a particular case of such states coincides with the squeezing of the carrier-envelope phase, or of the total intensity, of a mode-locked laser. We then discuss the experimental issues related to measuring the quantum noise of the carrier-envelope phase of a frequency comb and show that this can be carried out by use of quantum heterodyne multiplexing, a technique that may be useful to measure multipartite entanglement as well.
Frequency combs are multimode photonic systems that underlie countless precision sensing and metrology applications. Since their invention over two decades ago, numerous efforts have pushed frequency combs to broader bandwidths and more stable operation. More recently, quantum squeezing and entanglement have been explored in single frequency comb systems for quantum advantages in sensing and signal multiplexing. However, the production of quantum light across multiple frequency combs remains unexplored. In this work, we theoretically explore a mechanism that generates a series of nonlinearly coupled frequency combs through cascaded three-wave upconversion and downconversion processes mediated by a single idler comb. We show how this system generates inter- and intracomb two-mode squeezing and entanglement spanning a very large spectral range, from ultraviolet to mid-IR frequencies. Finally, we show how this system can be engineered to produce on-demand multimode quantum light through covariance matrix optimization. Our findings could enable tunable broadband ghost spectroscopy protocols, squeezing-enhanced pump-probe measurements, and broadband entanglement between spectrally-multiplexed quanta of information.
We show theoretically that multipartite entanglement is generated on a massive scale in the spectrum, or optical frequency comb, of a single optical parametric oscillator (OPO) emitting well above threshold. In this system, the quantum dynamics of the strongly depleted pump field are responsible for the onset of the entanglement by correlating the two-mode squeezed, bipartite-entangled pairs of OPO signal fields. (Such pairs are independent of one another in the undepleted, classical pump approximation.) We verify the multipartite nature of the entanglement by evaluating the van Loock-Furusawa criterion for a particular set of entanglement witnesses deduced from physical considerations.
We have developed a full multimode theory of a synchronously pumped type-I optical parametric oscillator. We calculate the output quantum fluctuations of the device and find that, in the degenerate case (coincident signal and idler set of frequencies), significant squeezing is obtained when one approaches threshold from below for a set of well-defined ``supermodes,'' or frequency combs, consisting of a coherent linear superposition of signal modes of different frequencies which are resonant in the cavity.