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

Optics Express

Temporal mode properties of Raman scattering in optical fibers

Nannan Liu, Jie Su, Yuhong Liu, Jiamin Li, Xiaoying Li

Published Apr 10, 2021• 4 citations
Publisher

Abstract

By investigating the intensity correlation function, we study the temporal mode properties of spontaneous Raman photons generated in single mode fibers pumped by short pulses. We find that the intensity correlation function of the Raman photons is related to the dispersion induced temporal mismatch among the Raman photons generated in different subparts of the fiber. When no temporal mismatch exists, the intensity correlation function only depends on the ratio between the pulse width of the pump and the coherence time of the Raman photons. With the ratio decreasing, the intensity correlation function increase. Our study is helpful for easily creating high-quality true thermal light which will be a useful resource for second-order coherence based remote sensing.

DOI
10.1364/oe.421222

Related papers

Evaluating dispersion of optical fiber by analyzing the temporal mode property of Raman scattering

Nannan Liu, Zhenming Dou, Yuhong Liu +2 more

We theoretically and experimentally demonstrate the influence of dispersion on the temporal mode properties of the spontaneous Raman scattering pumped by picosecond pulses in single mode optical fiber. We model the process of the ultrafast spontaneous Raman scattering, calculate and measure the intensity correlation function of the Raman photons with different dispersion by varying the detuning between pump and Raman photons or changing the optical length. The intensity correlation function decreases with the increase of dispersion induced temporal walk-off both by increasing the detuning and by increasing the fiber length. We evaluate the dispersion parameter of the single mode fiber by fitting the measured data with the theoretical equation we deduced. The estimated value is close to the labelled one. Our study provides a new way to evaluate dispersion parameters of the media in which Raman scattering can occur and is beneficial for efficient distillation of entanglement in optical fibers.

International Symposium on Ultrafast Phenomena and Terahertz Waves (ISUPTW)•Sep 9, 2021•0 citations

Stokes-anti-Stokes correlations of light propagating through weakly guiding optical fiber

Ivan V. Panyukov, E. S. Andrianov

Statistical properties of light produced in spontaneous Raman scattering on an ensemble of molecules indicate the quantum nature of this phenomenon. The scattered light is non-classical and has high non-classical intensity correlations between Stokes and anti-Stokes components. The temporal coherence of this light is well investigated, while many questions related to spatial coherence remain open. Recent experiments reveal two peculiar features of the spatial coherence of the Stokes and anti-Stokes light. First, the intensity correlations between Stokes and anti-Stokes light remain non-classical even for macroscopic samples containing many molecules. Second, these correlations decrease when signal propagates through a multi-mode optical fiber: the more propagating fiber modes at Stokes and anti-Stokes frequencies the less the correlations. Moreover, the second-order autocorrelation function of Stokes and anti-Stokes light also decreases with the number of propagating modes in multi-mode fiber. In this paper, we build a model of spontaneous Raman scattering correlations of light produced by an ensemble of molecules and propagating through weakly guiding optical fiber that quantitatively explains all these observations. We show that spacial orthogonality of the fiber modes makes the light propagating through these modes uncorrelated in the standard detection scheme. This leads to suppression of non-classical intensity correlations of the total field in the multi-mode fiber. We find the degree of non-classical correlations on fiber parameters. The obtained results pave the way for engineering of non-classical Stokes -- anti-Stokes correlations.

arXiv:2605.14825•May 14, 2026•0 citations

Effect of chromatic-dispersion-induced chirp on the temporal coherence properties of individual beams from spontaneous four-wave mixing

Xiaoxin Ma, Xiaoying Li, Liang Cui +2 more

Temporal coherence of individual signal or idler beam, determined by the spectral correlation property of photon pairs, is important for realizing quantum interference among independent sources. Based on spontaneous four-wave mixing in optical fibers, we study the effect of chirp on the temporal coherence property by introducing a different amount of chirp into either the pulsed pump or individual signal (idler) beam. The investigation shows that the pump chirp induces additional frequency correlation into photon pairs; the mutual spectral correlation of photon pairs and the coherence of individual beam can be characterized by measuring the intensity correlation function ${g}^{(2)}$ of the individual beam. To improve the coherence degree, the pump chirp should be minimized. Moreover, a Hong-Ou-Mandel--type two-photon interference experiment with the signal beams generated in two different fibers illustrates that the chirp of the individual signal (idler) beam does not change the temporal coherence degree, but affects the temporal mode matching. To achieve high visibility among multiple sources, apart from improving the coherence degree, mode matching should be optimized by managing the chirps of individual beams.

arXiv:1105.1490•Physical Review A•Aug 17, 2011•19 citations

Photon-pair generation in optical fibers through four-wave mixing: Role of Raman scattering and pump polarization

Qinglong Lin, Fatih Yaman, Govind Prasad Agrawal

We present a general quantum theory capable of describing photon statistics under the combined effects of four-wave mixing and Raman scattering inside optical fibers. Our theory is vectorial in nature and includes all polarization effects. Our analysis shows that spontaneous Raman scattering degrades the pair correlation in all cases but the extent of degradation depends on the pumping configuration employed. In a single-pump configuration, photon pairs can be created with polarization either parallel or orthogonal to the pump. Our results show that the orthogonal configuration can improve the extent of quantum correlation considerably over a broad bandwidth. In the case of a dual-pump configuration, we show that imbalance of two pump powers can be used to improve the quality of photon pairs. We show that orthogonally polarized pumps can generate photon pairs automatically in a polarization-entangled state. In particular, orthogonal pumping with circular polarizations produces such an entangled state with relatively high quality. We also quantify the quality of polarization entanglement as well as energy-time entanglement constructed using correlated photon pairs.

Physical Review A•Feb 1, 2007•206 citations

Generation of Quantum-Correlated Photon Pairs in Optical Fiber: Influence of Spontaneous Raman Scattering

Kyo Inoue, Kaoru Shimizu

The generation of quantum-correlated photon pairs by spontaneous four-wave mixing (FWM) in an optical fiber is studied. After demonstrating the time correlation between signal and idler photons, the influence of spontaneous Raman scattering on extracting photon pairs is experimentally investigated. It is shown that a short pulse and a narrow filtering bandwidth are preferable for obtaining correlated photon pairs with a better signal-to-noise ratio via FWM in an optical fiber.

Japanese Journal of Applied Physics•Dec 9, 2004•29 citations

Raman scattering effects on correlated photon-pair generation in chalcogenide

Alex S. Clark, Matthew J. Collins, Alexander C. Judge +3 more

In this paper we investigate uncorrelated noise from spontaneous Raman scattering (SpRS) and its effect on photon-pair generation in chalcogenide (As2S3). We measure a coincidence-to-accidental ratio (CAR) of 4.2 in a 7 cm As2S3 single-mode fiber, with enhancements from our previous result attributed to pulsed pumping and cooling. Using an analytical model we characterize the magnitude of the SpRS at different temperatures. Our analysis shows that even after cooling to liquid nitrogen temperature (77 K), SpRS is still significant. For large detunings from the pump, the dependence on temperature for the Stokes SpRS intensity becomes negligible, so cooling is not a complete solution to improve the quality of the photon source.

Optics Express•Jul 10, 2012•34 citations
By investigating the intensity correlation function, we study the temporal mode properties of spontaneous Raman photons generated in single mode fibers pumped by short pulses. We find that the intensity correlation function of the Raman photons is related to the dispersion induced temporal mismatch among the Raman photons generated in different subparts of the fiber. When no temporal mismatch exists, the intensity correlation function only depends on the ratio between the pulse width of the pump and the coherence time of the Raman photons. With the ratio decreasing, the intensity correlation function increase. Our study is helpful for easily creating high-quality true thermal light which will be a useful resource for second-order coherence based remote sensing.
We theoretically and experimentally demonstrate the influence of dispersion on the temporal mode properties of the spontaneous Raman scattering pumped by picosecond pulses in single mode optical fiber. We model the process of the ultrafast spontaneous Raman scattering, calculate and measure the intensity correlation function of the Raman photons with different dispersion by varying the detuning between pump and Raman photons or changing the optical length. The intensity correlation function decreases with the increase of dispersion induced temporal walk-off both by increasing the detuning and by increasing the fiber length. We evaluate the dispersion parameter of the single mode fiber by fitting the measured data with the theoretical equation we deduced. The estimated value is close to the labelled one. Our study provides a new way to evaluate dispersion parameters of the media in which Raman scattering can occur and is beneficial for efficient distillation of entanglement in optical fibers.
Statistical properties of light produced in spontaneous Raman scattering on an ensemble of molecules indicate the quantum nature of this phenomenon. The scattered light is non-classical and has high non-classical intensity correlations between Stokes and anti-Stokes components. The temporal coherence of this light is well investigated, while many questions related to spatial coherence remain open. Recent experiments reveal two peculiar features of the spatial coherence of the Stokes and anti-Stokes light. First, the intensity correlations between Stokes and anti-Stokes light remain non-classical even for macroscopic samples containing many molecules. Second, these correlations decrease when signal propagates through a multi-mode optical fiber: the more propagating fiber modes at Stokes and anti-Stokes frequencies the less the correlations. Moreover, the second-order autocorrelation function of Stokes and anti-Stokes light also decreases with the number of propagating modes in multi-mode fiber. In this paper, we build a model of spontaneous Raman scattering correlations of light produced by an ensemble of molecules and propagating through weakly guiding optical fiber that quantitatively explains all these observations. We show that spacial orthogonality of the fiber modes makes the light propagating through these modes uncorrelated in the standard detection scheme. This leads to suppression of non-classical intensity correlations of the total field in the multi-mode fiber. We find the degree of non-classical correlations on fiber parameters. The obtained results pave the way for engineering of non-classical Stokes -- anti-Stokes correlations.
Temporal coherence of individual signal or idler beam, determined by the spectral correlation property of photon pairs, is important for realizing quantum interference among independent sources. Based on spontaneous four-wave mixing in optical fibers, we study the effect of chirp on the temporal coherence property by introducing a different amount of chirp into either the pulsed pump or individual signal (idler) beam. The investigation shows that the pump chirp induces additional frequency correlation into photon pairs; the mutual spectral correlation of photon pairs and the coherence of individual beam can be characterized by measuring the intensity correlation function g(2){g}^{(2)}g(2) of the individual beam. To improve the coherence degree, the pump chirp should be minimized. Moreover, a Hong-Ou-Mandel--type two-photon interference experiment with the signal beams generated in two different fibers illustrates that the chirp of the individual signal (idler) beam does not change the temporal coherence degree, but affects the temporal mode matching. To achieve high visibility among multiple sources, apart from improving the coherence degree, mode matching should be optimized by managing the chirps of individual beams.
We present a general quantum theory capable of describing photon statistics under the combined effects of four-wave mixing and Raman scattering inside optical fibers. Our theory is vectorial in nature and includes all polarization effects. Our analysis shows that spontaneous Raman scattering degrades the pair correlation in all cases but the extent of degradation depends on the pumping configuration employed. In a single-pump configuration, photon pairs can be created with polarization either parallel or orthogonal to the pump. Our results show that the orthogonal configuration can improve the extent of quantum correlation considerably over a broad bandwidth. In the case of a dual-pump configuration, we show that imbalance of two pump powers can be used to improve the quality of photon pairs. We show that orthogonally polarized pumps can generate photon pairs automatically in a polarization-entangled state. In particular, orthogonal pumping with circular polarizations produces such an entangled state with relatively high quality. We also quantify the quality of polarization entanglement as well as energy-time entanglement constructed using correlated photon pairs.
In this paper we investigate uncorrelated noise from spontaneous Raman scattering (SpRS) and its effect on photon-pair generation in chalcogenide (As2S3). We measure a coincidence-to-accidental ratio (CAR) of 4.2 in a 7 cm As2S3 single-mode fiber, with enhancements from our previous result attributed to pulsed pumping and cooling. Using an analytical model we characterize the magnitude of the SpRS at different temperatures. Our analysis shows that even after cooling to liquid nitrogen temperature (77 K), SpRS is still significant. For large detunings from the pump, the dependence on temperature for the Stokes SpRS intensity becomes negligible, so cooling is not a complete solution to improve the quality of the photon source.