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

Physical Review A

Twin beams, nonlinearity, and walk-off in optical parametric oscillators

Roberta Zambrini, Maxi San Miguel

Published Aug 8, 2002• 13 citations
Publisher

Abstract

We study the quantum properties of the spatially tilted macroscopic signal beams in the transverse pattern formed in a degenerate optical parametric oscillator above threshold. We show that walk-off leads to an imbalance in the intensities and fluctuations of these beams when nonlinear multimode interactions are effective. Still, quantum correlations between the two beams are preserved, so that their intensity difference exhibits sub-Poissonian statistics.

DOI
10.1103/physreva.66.023807

Related papers

Polarization quantum properties in a type-II optical parametric oscillator below threshold

Roberta Zambrini, A. Gatti, Luigi Lugiato +1 more

We study the far-field spatial distribution of the quantum fluctuations in the transverse profile of the output light beam generated by a type-II optical parametric oscillator below threshold, including the effects of transverse walk-off. We study how quadrature field correlations depend on the polarization. We find spatial Einstein-Podolsky-Rosen entanglement in quadrature-polarization components. For the far-field points not affected by walk-off there is almost complete noise suppression in the proper quadratures difference of any orthogonal polarization components. We show the entanglement of the state of symmetric, intense, or macroscopic, spatial light modes. We also investigate nonclassical polarization properties in terms of the Stokes operators. We find perfect correlations in all Stokes parameters measured in opposite far-field points in the direction orthogonal to the walk-off, while locally the field is unpolarized and we find no polarization squeezing.

arXiv:quant-ph/0306134•Physical Review A•Dec 10, 2003•10 citations

Generation of Quantum-Correlated Twin Beams and Its Application

Katsuyuki Kasai

The signal and idler beams from a non-degenerate, above threshold, optical parametric oscillator have a strong quantum correlation, which are called twin beams. This correlation arises from the simultaneous generation of the signal and idler photons in the form of twin pairs of photons through the parametric down conversion, and the generated twin beams have exactly the same photon statistics. As a result, the fluctuations on the difference between the intensities of the twin beams are reduced with respect to the shot noise limit, that is, intensity-difference squeezing. We give a comprehensive overview of the generation of twin beams using the optical parametric oscillator, and the applications exploiting the quantum correlation of twin beams are presented.

The Review of Laser Engineering•Jan 1, 2003•0 citations

Simultaneous measurement of patterns in the signal and idler near and far fields from a confocal optical parametrical oscillator with applications in quantum optics

Mikael Lassen, Peter Tidemand‐Lichtenberg, Preben Buchhave

We present the results of an experimental investigation of multimode intensity patterns from an optical parametric oscillator operating above threshold and show that it oscillates in 10--15 transverse modes strongly coupled through the nonlinear crystal, which makes this setup useful for future investigation of quantum correlations in the transverse plane. We describe the experimental setup for simultaneous measurements of signal and idler near- and far-field patterns and analyze the effects of various experimental complications such as walk-off and thermal index changes on the generated patterns. We also show that the oscillator can be stabilized by optical feedback, indicating a possible route for controlling the generated intensity patterns.

Physical Review A•Aug 18, 2005•4 citations

Quantum correlation in multimode OPO

Mikael Lassen, Preben Buchhave

Fluctuations in the field of a 2nd order nonlinear multi-mode parametric downcoverter exhibit nonclassical correlations in the transverse plane. We present results of measurements of the classical pattern for a degenerate, multi-mode parametric optical parametric oscillator (OPO) operating above threshold. We also present results of autocorrelation measurements of intensity fluctuations in the transverse plane both in the near field and in the far field with the OPO operating both below and above threshold -- a method we believe will ultimately enable us to display the nonclassical correlations of the OPO output.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•May 25, 2004•0 citations

Experimental study of the spatial distribution of quantum correlations in a confocal optical parametric oscillator

M. Martinelli, Nicolas Treps, S. Ducci +3 more

We study experimentally the spatial distribution of quantum noise in the twin beams produced by a type-II optical parametric oscillator operating in a confocal cavity above threshold. The measured intensity correlations are at the same time below the standard quantum limit and not uniformly distributed inside the beams. We show that this feature is an unambiguous evidence for the multimode and nonclassical character of the quantum state generated by the device.

arXiv:quant-ph/0210023•Physical Review A•Feb 13, 2003•56 citations

Langevin treatment of quantum fluctuations and optical patterns in optical parametric oscillators below threshold

A. Gatti, H. Wiedemann, Luigi A. Lugiato +3 more

A Langevin model is introduced to study quantum fluctuations below the threshold of pattern formation for optical parametric oscillators (OPO's). In particular we compare analytical and numerical results for the OPO with one and two transverse spatial dimensions and in the presence of either plane or spherical cavity mirrors. The far-field structure and the correlation functions of the fluctuating signal field anticipate the onset of a transverse spatial pattern which arises classically even in the presence of Gaussian input beams. Correlation functions also reveal the squeezed nature of the OPO field. Numerical simulations of the Langevin model describe the result of short time measurements and show that close to threshold the near-field signal is a noisy spot pattern evolving on a time scale longer than the inverse decay rate of the resonator. This and other far-field features should be experimentally accessible.

Physical Review A•Jul 1, 1997•105 citations
We study the quantum properties of the spatially tilted macroscopic signal beams in the transverse pattern formed in a degenerate optical parametric oscillator above threshold. We show that walk-off leads to an imbalance in the intensities and fluctuations of these beams when nonlinear multimode interactions are effective. Still, quantum correlations between the two beams are preserved, so that their intensity difference exhibits sub-Poissonian statistics.
We study the far-field spatial distribution of the quantum fluctuations in the transverse profile of the output light beam generated by a type-II optical parametric oscillator below threshold, including the effects of transverse walk-off. We study how quadrature field correlations depend on the polarization. We find spatial Einstein-Podolsky-Rosen entanglement in quadrature-polarization components. For the far-field points not affected by walk-off there is almost complete noise suppression in the proper quadratures difference of any orthogonal polarization components. We show the entanglement of the state of symmetric, intense, or macroscopic, spatial light modes. We also investigate nonclassical polarization properties in terms of the Stokes operators. We find perfect correlations in all Stokes parameters measured in opposite far-field points in the direction orthogonal to the walk-off, while locally the field is unpolarized and we find no polarization squeezing.
The signal and idler beams from a non-degenerate, above threshold, optical parametric oscillator have a strong quantum correlation, which are called twin beams. This correlation arises from the simultaneous generation of the signal and idler photons in the form of twin pairs of photons through the parametric down conversion, and the generated twin beams have exactly the same photon statistics. As a result, the fluctuations on the difference between the intensities of the twin beams are reduced with respect to the shot noise limit, that is, intensity-difference squeezing. We give a comprehensive overview of the generation of twin beams using the optical parametric oscillator, and the applications exploiting the quantum correlation of twin beams are presented.
We present the results of an experimental investigation of multimode intensity patterns from an optical parametric oscillator operating above threshold and show that it oscillates in 10--15 transverse modes strongly coupled through the nonlinear crystal, which makes this setup useful for future investigation of quantum correlations in the transverse plane. We describe the experimental setup for simultaneous measurements of signal and idler near- and far-field patterns and analyze the effects of various experimental complications such as walk-off and thermal index changes on the generated patterns. We also show that the oscillator can be stabilized by optical feedback, indicating a possible route for controlling the generated intensity patterns.
Fluctuations in the field of a 2nd order nonlinear multi-mode parametric downcoverter exhibit nonclassical correlations in the transverse plane. We present results of measurements of the classical pattern for a degenerate, multi-mode parametric optical parametric oscillator (OPO) operating above threshold. We also present results of autocorrelation measurements of intensity fluctuations in the transverse plane both in the near field and in the far field with the OPO operating both below and above threshold -- a method we believe will ultimately enable us to display the nonclassical correlations of the OPO output.
A Langevin model is introduced to study quantum fluctuations below the threshold of pattern formation for optical parametric oscillators (OPO's). In particular we compare analytical and numerical results for the OPO with one and two transverse spatial dimensions and in the presence of either plane or spherical cavity mirrors. The far-field structure and the correlation functions of the fluctuating signal field anticipate the onset of a transverse spatial pattern which arises classically even in the presence of Gaussian input beams. Correlation functions also reveal the squeezed nature of the OPO field. Numerical simulations of the Langevin model describe the result of short time measurements and show that close to threshold the near-field signal is a noisy spot pattern evolving on a time scale longer than the inverse decay rate of the resonator. This and other far-field features should be experimentally accessible.