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

International Conference on Transparent Optical Networks

Detrimental effects in four wave mixing

Karsten K. Rottwitt, Thjalfe Ulvenberg, Lars Søgaard Rishøj, Jacob G. Koefoed, Lars Grüner-Nielsen

Published Jul 14, 2024• 0 citations
Publisher

Abstract

Four wave mixing (FWM) holds great promise as a tool to perform signal processing of classical light as well as of quantum states. However, typically FWM require use of high power pumps and as a consequence, the FWM process is accompanied by spontaneous Raman scattering as well as spontaneous FWM. In addition, FWM is also very sensitive to changes in the phase matching along propagation, caused by fluctuations in the core geometry of the fiber. In this work, we review recent progress in predicting and measuring the conversion efficiency and noise figure of wavelength conversion using FWM and we show consequences due fluctuations in the core geometry.

DOI
10.1109/icton62926.2024.10647360

Related papers

Phase matching for spontaneous frequency conversion via four-wave mixing in graded-index multimode optical fibers

Elham S. Nazemosadat, Hamed Pourbeyram, Arash Mafi

A detailed analysis of four-wave mixing (FWM) and its required phase-matching conditions in graded-index multimode optical fibers is presented. The analysis is relevant mainly for spontaneous frequency conversion and photon pair generation via FWM, when the fiber length is of the order of a meter or shorter, and the signal and idler are generated at large frequency separations from the pump. An analytic expression for calculating the phase mismatch occurring as a result of the waveguide dispersion among the pump, signal, and idler beams is derived, and it agrees well with independent numerical analysis. This expression simplifies calculations considerably, as it allows the prediction of the wavelengths of the signal and idler by using only the mode group number of the spatial modes involved in the FWM process and the refractive index profile of the fiber. The scaling of the signal–pump–idler frequency separations with the mode group numbers is explored. The abundance of the configuration degeneracies of the FWM process in graded-index multimode fibers indicates that nearly identical signal and idler frequencies can be obtained for many different pump, signal, and idler spatial mode profile combinations.

Journal of the Optical Society of America B•Jan 6, 2016•90 citations

Nonlinear Optical Signal Processing and Generation of Quantum States using Intermodal Four-wave Mixing

Karsten K. Rottwitt, Mario A. Usuga Castaneda, Erik Nicolai Christensen +2 more

The strong interest in space-division multiplexing of classical communication signals has resulted in development of optical fibers that support propagation of multiple modes. This has paved the way for progress in signal processing using multiple modes and four-wave mixing between these. More specifically, careful design and knowledge of optical properties of individual modes enables phase matching in four-wave mixing that is otherwise not possible with single-mode fibers. This enables signal processing using four-wave mixing between higher-order modes for e.g. frequency conversion over a wide bandwidth. In addition, processing and creation of quantum states has also been demonstrated using four-wave mixing, including generation of photon pairs. In this work we review recent progress in signal processing and generation of quantum states using four-wave mixing.

International Conference on Transparent Optical Networks•Jul 1, 2018•1 citation

Signal Processing using Nonlinear Optical Eects in Single- and Few-Mode Fibers

Søren Friis

The stagnating increase in data transmission capacity in optical communication systems combined with the ever growing demand of transmission bandwidth is leading to an impending capacity crunch, referring to the point in time after which the available bandwidth of the individual user starts to decrease. To postpone this point in time, existing technologies in terms of data transmission through optical fibers must be optimized and new degrees of freedom must be introduced to continue the exponential increase in available bandwidth; space-division multiplexing is believed to be the strongest candidate for another degree of freedom in transmission fibers. This thesis is two-fold: firstly, starting at Maxwell’s equations and basic principles of quantum mechanics, a semi-classical model of the noise properties of fiber optical parametric amplifiers and frequency converters is presented. The model accounts for multiple effects present in nonlinear fibers such as four-wave mixing, Raman scattering, distributed loss, and dispersion, and it is valid in the depleted pump regime. After validating the model against well-known results of quantum models, the model is used to predict the impacts of Raman noise, loss, and pump depletion on the noise properties of parametric frequency conversion and phase-insensitive and phase-sensitive parametric amplification. An important part of realizing space-division multiplexing is the ability of optical signal processing so the second part of this thesis addresses few-mode Raman fiber amplifiers and parametric amplifiers and frequency converters. A model of weak random linear mode coupling in the pump of a two-mode distributed Raman fiber amplifier is presented and it is shown that an amplification noise figure induced by mode coupling increases with the degree of mode coupling and that this tendency increases as the pump depletes. Also, a very low mode-dependent gain of 0.25 dB per 10 dB gain is experimentally demonstrated in a two-mode distributed Raman fiber amplifier by exciting the pump in a combination of two modes. A comprehensive model of four-wave mixing in two-mode fibers acvi counting for six simultaneous processes is derived, and the conversion efficiency from signal to idler in the four-wave mixing processes of phase conjugation and Bragg scattering in two two-mode fibers with different phase matching properties are experimentally investigated. A conversion efficiency of > −2.70 dB is demonstrated for Bragg scattering in the conversion of a signal in the LP01-mode to the idler in the LP11-mode; the signal-to-idler separation is ∼ 25 nm. Good qualitative agreement between experiments and theory is found for both processes in both fibers.

•Jan 1, 2016•0 citations

180-nm wavelength conversion based on Bragg scattering in an optical fiber

David Méchin, Richard Provo, J.D. Harvey +1 more

Efficient, wideband and tunable optical wavelength conversion over 180 nm by four-wave mixing (Bragg scattering) in a fiber is demonstrated experimentally. This process has the potential to translate optical data (states of light) without the noise pollution associated with parametric amplification and spontaneous Raman scattering.

Optics Express•Jan 1, 2006•53 citations

Quantum Information Processing Using Intermodal Four-Wave Mixing in Multi-Mode Optical Fibers

Karsten K. Rottwitt, Jesper B. Christensen, Erik Nicolai Christensen +1 more

Being able to generate and process quantum states are essential functionalities in quantum communication. Examples of the processing include conversion of the wavelength of quantum states or modification of their temporal shape. The combined use of four-wave mixing and higher order modes in optical fibers has enabled such functionalities. The use of intermodal four-wave mixing among higher order modes, enable frequency conversion over a wavelength bandwidth, large enough to avoid spontaneous Raman scattering, which is otherwise detrimental for quantum communication. The process of intermodal four-wave mixing furthermore has the advantage that the same process may be used to generate single photon states. We review recent results on the use of intermodal four-wave mixing in optical multi-mode fibers for quantum information science and show a theoretical/numerical model that may be used to predict the performance of quantum state processing devices based on four-wave mixing.

International Conference on Transparent Optical Networks•Jul 1, 2019•1 citation

Influence of multiple four-wave-mixing processes on quantum noise of dual-pump phase-sensitive amplification in a fiber

Kyo Inoue

Phase-sensitive amplification (PSA) based on nonlinear parametric interaction provides low-noise amplification such that the noise figure can be 0 dB in principle. However, when an optical fiber is used as a nonlinear medium for PSA, multiple four-wave-mixing (FWM) processes other than the PSA process are induced, which can degrade the PSA noise performance, especially in dual-pump PSA with a narrow signal-pump wavelength separation. This paper investigates the influence of multiple FWM processes on quantum noise of dual-pump PSA in an optical fiber. The noise figure is calculated using quantum-mechanical operators, considering multiple FWM processes with the PSA process. Calculation examples are also presented, which indicate that the noise figure is degraded by 0.2–0.4 dB from the ideal 0 dB, depending on the signal-pump wavelength separation and fiber parameters.

Journal of the Optical Society of America B•May 10, 2019•10 citations
Four wave mixing (FWM) holds great promise as a tool to perform signal processing of classical light as well as of quantum states. However, typically FWM require use of high power pumps and as a consequence, the FWM process is accompanied by spontaneous Raman scattering as well as spontaneous FWM. In addition, FWM is also very sensitive to changes in the phase matching along propagation, caused by fluctuations in the core geometry of the fiber. In this work, we review recent progress in predicting and measuring the conversion efficiency and noise figure of wavelength conversion using FWM and we show consequences due fluctuations in the core geometry.
A detailed analysis of four-wave mixing (FWM) and its required phase-matching conditions in graded-index multimode optical fibers is presented. The analysis is relevant mainly for spontaneous frequency conversion and photon pair generation via FWM, when the fiber length is of the order of a meter or shorter, and the signal and idler are generated at large frequency separations from the pump. An analytic expression for calculating the phase mismatch occurring as a result of the waveguide dispersion among the pump, signal, and idler beams is derived, and it agrees well with independent numerical analysis. This expression simplifies calculations considerably, as it allows the prediction of the wavelengths of the signal and idler by using only the mode group number of the spatial modes involved in the FWM process and the refractive index profile of the fiber. The scaling of the signal–pump–idler frequency separations with the mode group numbers is explored. The abundance of the configuration degeneracies of the FWM process in graded-index multimode fibers indicates that nearly identical signal and idler frequencies can be obtained for many different pump, signal, and idler spatial mode profile combinations.
The strong interest in space-division multiplexing of classical communication signals has resulted in development of optical fibers that support propagation of multiple modes. This has paved the way for progress in signal processing using multiple modes and four-wave mixing between these. More specifically, careful design and knowledge of optical properties of individual modes enables phase matching in four-wave mixing that is otherwise not possible with single-mode fibers. This enables signal processing using four-wave mixing between higher-order modes for e.g. frequency conversion over a wide bandwidth. In addition, processing and creation of quantum states has also been demonstrated using four-wave mixing, including generation of photon pairs. In this work we review recent progress in signal processing and generation of quantum states using four-wave mixing.
The stagnating increase in data transmission capacity in optical communication systems combined with the ever growing demand of transmission bandwidth is leading to an impending capacity crunch, referring to the point in time after which the available bandwidth of the individual user starts to decrease. To postpone this point in time, existing technologies in terms of data transmission through optical fibers must be optimized and new degrees of freedom must be introduced to continue the exponential increase in available bandwidth; space-division multiplexing is believed to be the strongest candidate for another degree of freedom in transmission fibers. This thesis is two-fold: firstly, starting at Maxwell’s equations and basic principles of quantum mechanics, a semi-classical model of the noise properties of fiber optical parametric amplifiers and frequency converters is presented. The model accounts for multiple effects present in nonlinear fibers such as four-wave mixing, Raman scattering, distributed loss, and dispersion, and it is valid in the depleted pump regime. After validating the model against well-known results of quantum models, the model is used to predict the impacts of Raman noise, loss, and pump depletion on the noise properties of parametric frequency conversion and phase-insensitive and phase-sensitive parametric amplification. An important part of realizing space-division multiplexing is the ability of optical signal processing so the second part of this thesis addresses few-mode Raman fiber amplifiers and parametric amplifiers and frequency converters. A model of weak random linear mode coupling in the pump of a two-mode distributed Raman fiber amplifier is presented and it is shown that an amplification noise figure induced by mode coupling increases with the degree of mode coupling and that this tendency increases as the pump depletes. Also, a very low mode-dependent gain of 0.25 dB per 10 dB gain is experimentally demonstrated in a two-mode distributed Raman fiber amplifier by exciting the pump in a combination of two modes. A comprehensive model of four-wave mixing in two-mode fibers acvi counting for six simultaneous processes is derived, and the conversion efficiency from signal to idler in the four-wave mixing processes of phase conjugation and Bragg scattering in two two-mode fibers with different phase matching properties are experimentally investigated. A conversion efficiency of > −2.70 dB is demonstrated for Bragg scattering in the conversion of a signal in the LP01-mode to the idler in the LP11-mode; the signal-to-idler separation is ∼ 25 nm. Good qualitative agreement between experiments and theory is found for both processes in both fibers.
Being able to generate and process quantum states are essential functionalities in quantum communication. Examples of the processing include conversion of the wavelength of quantum states or modification of their temporal shape. The combined use of four-wave mixing and higher order modes in optical fibers has enabled such functionalities. The use of intermodal four-wave mixing among higher order modes, enable frequency conversion over a wavelength bandwidth, large enough to avoid spontaneous Raman scattering, which is otherwise detrimental for quantum communication. The process of intermodal four-wave mixing furthermore has the advantage that the same process may be used to generate single photon states. We review recent results on the use of intermodal four-wave mixing in optical multi-mode fibers for quantum information science and show a theoretical/numerical model that may be used to predict the performance of quantum state processing devices based on four-wave mixing.
Phase-sensitive amplification (PSA) based on nonlinear parametric interaction provides low-noise amplification such that the noise figure can be 0 dB in principle. However, when an optical fiber is used as a nonlinear medium for PSA, multiple four-wave-mixing (FWM) processes other than the PSA process are induced, which can degrade the PSA noise performance, especially in dual-pump PSA with a narrow signal-pump wavelength separation. This paper investigates the influence of multiple FWM processes on quantum noise of dual-pump PSA in an optical fiber. The noise figure is calculated using quantum-mechanical operators, considering multiple FWM processes with the PSA process. Calculation examples are also presented, which indicate that the noise figure is degraded by 0.2–0.4 dB from the ideal 0 dB, depending on the signal-pump wavelength separation and fiber parameters.