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

SPIE Conference on Nonlinear Optics and its Applications

Photorefractive slow light at 1310nm

Nacera Bouldja, A. A. Grabar, Marc Sciamanna, Delphine Wolfersberger

Published Jun 20, 2024• 0 citations
Publisher

Abstract

In this work, we experimentally demonstrate the capacity of the photorefractive (PR) crystal to control the group velocity of light pulses, specifically at the telecommunication wavelength, by using the so-called beam fanning at room temperature. Significantly, we show for the first time that this method can effectively decelerate a modulated signal propagating through this material at 1310 nm. Furthermore, we illustrate that the performance of this slow light system can be adjusted by changing the intensity, duration, and angle of polarization of the input pulse. The results obtained through this technique can potentially improve the performance of specific components in telecommunication networks.

DOI
10.1117/12.3022292

Related papers

Slow light using photorefractive nonlinear optics

Nacera Bouldja, Marc Sciamanna, Delphine Wolfersberger

Slow and fast light are achieved in two experiments using SPS photorefractive crystal at room temperature. We report that the photorefractive gain achieved by the two wave mixing (TWM) method can control the group velocity of the transmitted light pulses at visible wavelength. It is shown theoretically and experimentally that the time delay and the shape of the output pulse change as a function of the photorefractive gain. The beam fanning has also been used to control the velocity propagation of a single light pulse in the same crystal at λ = 1064 nm. Depending on the orientation of the polar axis, it is possible to accelerate or decelerate a short pulse with duration of order of μs in the crystal.

SPIE Conference on Nonlinear Optics and its Applications•Apr 1, 2020•0 citations

Zero-broadening slow light from photorefractive two-wave mixing

Nacera Bouldja, Marc Sciamanna, A. A. Grabar +1 more

The ability to delay short light pulses is a promising solution for all-optical telecommunications, but suffers from a large distortion of the delayed pulse as a consequence of the high material dispersion. In this Letter, we demonstrate the possibility to all-optically control the group delay in a photorefractive (PR) crystal by the use of the two-wave mixing (TWM) effect in the pulse regime at room temperature. Most importantly, we show that a proper choice of the pump pulse width in the TWM process enables us to slow down shorter or longer signal pulses without distortion. The technique is demonstrated both at visible (638 nm) and infrared (1064 nm) wavelengths and for slowed-down pulses with durations ranging from 10 ns up to 30 ms, hence confirming its broad applicability.

Optics Letters•Aug 28, 2023•2 citations

Slow light with photorefractive beam fanning

Nacera Bouldja, Marc Sciamanna, Delphine Wolfersberger

The beam fanning naturally occurring in a photorefractive crystal is shown to slow down a single light pulse at room temperature. Slow light is demonstrated for both visible and infrared wavelength light pulses as short as the response time of the photorefractive crystal and with fractional delay- i.e ratio of delay to output pulse duration- up to 0.4.

Optics Express•Jan 30, 2020•7 citations

Slowdown of nanosecond light pulses with photorefractive two-wave mixing

Nacera Bouldja, Михайло Володимирович Цигика, A. A. Grabar +2 more

In the demonstrations of slow light in photorefractive (PR) materials, the delays are only reported for long pulse durations (ms to s) that are in discrepancy with typical ns-pulse length in data processing applications. Here we demonstrate that the slowdown of light in a PR crystal can be also achieved in the nanosecond regime at room temperature. We experimentally show that the use of a pulsed laser with a high peak intensity may indeed reduce the ${\mathrm{Sn}}_{2}{\mathrm{P}}_{2}{\mathrm{S}}_{6}$ crystal response time to a scale of ns and achieve a two-wave mixing (TWM) gain of $7.9\phantom{\rule{4pt}{0ex}}{\text{cm}}^{\ensuremath{-}1}$. We show the slowdown of light pulses whose duration ranges from 10 to 100 ns with a fractional delay up to 0.3. These results are similar to those obtained in optical fibers, except that the slow light with PR TWM is achieved through smaller propagation lengths and at wide wavelength ranges. This could reveal potential applications of PR slow light systems and have a significant impact for future optical communications systems.

Physical Review A•Feb 3, 2022•6 citations

All-optical tunable slow-light systems based on a TWM in a photorefractive crystal

Nacera Bouldja, Marc Sciamanna, A. A. Grabar +1 more

We experimentally propose a technique to demonstrate an optical slow-light system using the two-wave mixing (TWM) process in a photorefractive (PR) crystal at room temperature. This technique uses the refractive index variation that occurs in the PR material at room temperature. In this paper, we show that the time delay and the bandwidth of the transmitted pulses can be easily tuned by varying both laser beam intensities and the widths of the input pulses. In addition, time delays of short light pulses are observed with modest pulse distortions at the output of the PR crystal using a pulsed laser at the nanosecond regime.

Optical and Quantum Sensing and Precision Metrology II•Mar 8, 2023•0 citations

Slow Light using Photorefractive Beam Fanning

Nacera Bouldja, Marc Sciamanna, Delphine Wolfersberger

Slow-down of the light velocity has potential applications in information processing [1] and interferometers. Recently, several works have experimentally [2] demonstrated the deceleration of light in photorefractive crystals using a two wave mixing (TWM). A low velocity value of the order of 0.02 cm/s has been reported in BaTiO3crystal for Gaussian pulse profiles of long duration of 1.3 s [3]. It was also reported that the time delay depends mainly on the coupling photorefractive gain. However, the photorefractive grating build-up time in that crystal does not allow to slow down pulses shorter than ms, which limits its interest for telecoms applications.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 1, 2019•0 citations
In this work, we experimentally demonstrate the capacity of the photorefractive (PR) crystal to control the group velocity of light pulses, specifically at the telecommunication wavelength, by using the so-called beam fanning at room temperature. Significantly, we show for the first time that this method can effectively decelerate a modulated signal propagating through this material at 1310 nm. Furthermore, we illustrate that the performance of this slow light system can be adjusted by changing the intensity, duration, and angle of polarization of the input pulse. The results obtained through this technique can potentially improve the performance of specific components in telecommunication networks.
Slow and fast light are achieved in two experiments using SPS photorefractive crystal at room temperature. We report that the photorefractive gain achieved by the two wave mixing (TWM) method can control the group velocity of the transmitted light pulses at visible wavelength. It is shown theoretically and experimentally that the time delay and the shape of the output pulse change as a function of the photorefractive gain. The beam fanning has also been used to control the velocity propagation of a single light pulse in the same crystal at λ = 1064 nm. Depending on the orientation of the polar axis, it is possible to accelerate or decelerate a short pulse with duration of order of μs in the crystal.
The ability to delay short light pulses is a promising solution for all-optical telecommunications, but suffers from a large distortion of the delayed pulse as a consequence of the high material dispersion. In this Letter, we demonstrate the possibility to all-optically control the group delay in a photorefractive (PR) crystal by the use of the two-wave mixing (TWM) effect in the pulse regime at room temperature. Most importantly, we show that a proper choice of the pump pulse width in the TWM process enables us to slow down shorter or longer signal pulses without distortion. The technique is demonstrated both at visible (638 nm) and infrared (1064 nm) wavelengths and for slowed-down pulses with durations ranging from 10 ns up to 30 ms, hence confirming its broad applicability.
In the demonstrations of slow light in photorefractive (PR) materials, the delays are only reported for long pulse durations (ms to s) that are in discrepancy with typical ns-pulse length in data processing applications. Here we demonstrate that the slowdown of light in a PR crystal can be also achieved in the nanosecond regime at room temperature. We experimentally show that the use of a pulsed laser with a high peak intensity may indeed reduce the Sn2P2S6{\mathrm{Sn}}_{2}{\mathrm{P}}_{2}{\mathrm{S}}_{6}Sn2​P2​S6​ crystal response time to a scale of ns and achieve a two-wave mixing (TWM) gain of $7.9\phantom{\rule{4pt}{0ex}}{\text{cm}}^{\ensuremath{-}1}$. We show the slowdown of light pulses whose duration ranges from 10 to 100 ns with a fractional delay up to 0.3. These results are similar to those obtained in optical fibers, except that the slow light with PR TWM is achieved through smaller propagation lengths and at wide wavelength ranges. This could reveal potential applications of PR slow light systems and have a significant impact for future optical communications systems.
We experimentally propose a technique to demonstrate an optical slow-light system using the two-wave mixing (TWM) process in a photorefractive (PR) crystal at room temperature. This technique uses the refractive index variation that occurs in the PR material at room temperature. In this paper, we show that the time delay and the bandwidth of the transmitted pulses can be easily tuned by varying both laser beam intensities and the widths of the input pulses. In addition, time delays of short light pulses are observed with modest pulse distortions at the output of the PR crystal using a pulsed laser at the nanosecond regime.
Slow-down of the light velocity has potential applications in information processing [1] and interferometers. Recently, several works have experimentally [2] demonstrated the deceleration of light in photorefractive crystals using a two wave mixing (TWM). A low velocity value of the order of 0.02 cm/s has been reported in BaTiO3crystal for Gaussian pulse profiles of long duration of 1.3 s [3]. It was also reported that the time delay depends mainly on the coupling photorefractive gain. However, the photorefractive grating build-up time in that crystal does not allow to slow down pulses shorter than ms, which limits its interest for telecoms applications.