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

Journal of the Optical Society of America B

Slowdown and speedup of light pulses using the self-compensating photorefractive response

Boris I. Sturman, P. Mathey, Hans Rudolf Jauslin

Published Feb 1, 2011• 13 citations
Publisher

Abstract

We study theoretically the effects of pulse slowdown and speedup in ferroelectric Sn2P2S6 possessing a self-compensating photorefractive response. It is shown that both these effects can be implemented in one sample for sufficiently large values of the coupling strength. In contrast to other types of the photorefractive response (local and nonlocal), the output pulses do not suffer from strong spatial amplification and broadening.

DOI
10.1364/josab.28.000347

Related papers

Light pulse amplification by photorefractive two-wave mixing

Evgeniy V. Podivilov, Boris I. Sturman, Alexander N. Shumelyuk +1 more

It has been shown recently (see, e.g., Nature, 397, 594, 1999; 409, 490, 2001) that light pulses can be remarkably slowed down in resonant gases under very low temperatures. We show theoretically and experimentally that a similar in nature (and stronger in value) phenomenon occurs in photorefractive nonlinear media. The pulse-maximum velocity can be reduced here to the value of thickness/response time because of the two wave coupling effect. Specific properties of pulse propagation depend on the type of the photorefractive response and also duration and shape of the input pulse. Our theoretical results for the nonlocal nonlinear response are in a good agreement with experimental data obtained with BaTiO3 and Sn2P2S6 crystals.

Photorefractive Effects, Materials, and Devices•Jan 1, 2003•0 citations

Photorefractive deceleration of light pulses

Boris I. Sturman, Evgeniy V. Podivilov, M. V. Gorkunov

We theoretically study the effect of light deceleration in photorefractive nonlinear media. This includes consideration of different types of the photorefractive nonlinear response, different wave interaction schemes, and an analysis of the influence of the input parameters, such as the input temporal pulse width and the coupling strength, on the output pulse characteristics: the time delay, the propagation velocity, the amplification factor, and the output width. We show that photorefractive light deceleration has numerous advantages over other known techniques. It works already at low intensities, at room temperature, and within wide spectral ranges and offers a vast variety of handles for manipulating light pulses. An analogy with the light deceleration method based on the quantum effect of electromagnetically induced transparency in ultracold resonant gases is also considered.

Journal of Experimental and Theoretical Physics•Apr 1, 2008•2 citations

Manipulation of fast light using photorefractive beam fanning

A. A. Grabar, P. Mathey, Grégory Gadret

Light pulse group velocity manipulations due to the specific dispersion of a medium (so-called “slow” and “fast” light phenomena) can be obtained on the basis of several mechanisms. One of these techniques is two-wave mixing in a photorefractive crystal. This work presents a modification of this method, exploiting the strong beam fanning in Sb-doped Sn2P2S6 crystals. Our experimental results demonstrate a “fast light” behavior of Gaussian pulses transmitted through a Sn2P2S6:Sb sample. The phenomenon is due to the beam fanning (i.e., the self-diffraction of the incident beam on self-induced noisy photorefractive gratings) that ensures a significant depletion of the input beam. Due to the relatively fast photorefractive response of the Sn2P2S6:Sb crystals this depletion occurs with times in the range of 10–100 ms, depending on the beam intensity, and the “fast light” feature is observed. The temporal and amplitude characteristics of the output beam are measured in function of the intensity and polarization azimuth of the incident beam. Besides, a negative phase shift of the periodical output beam relative to a sinusoidal intensity-modulated input beam is also obtained experimentally. It is shown that the phase and amplitude relation between the input and output periodic signals are described by a simple analytical expression that takes into account the beam fanning strength (depletion factor) and its dynamics (depletion time constant). It is also demonstrated that the pulse advance (or phase shift of the modulated signal) can be regulated by the light polarization azimuth. The advantages of the proposed method are discussed.

Journal of the Optical Society of America B•Apr 4, 2014•14 citations

Photorefractive induced slowdown of nanosecond light pulses in the nanosecond regime

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

Recently, several works have shown that the light group velocity can be reduced using the recording of dynamic refractive index gratings in photorefractive (PR) crystals [1] , [2] , [3] . The slowdown of light is performed using optical beams wave mixing: it yields the output pulse amplification and increases the light dispersion inside the PR crystal. For example, the TWM method demonstrated that the delay time ∆ τ can be varied as a function of the TWM gain values Γ and the input pulse widths T 0 . However, several works have shown that the results achieved by this method are limited in terms of pulse duration. Indeed, only long pulses with time duration of ms−s can be slowdown in a PR crystal both at the visible and the infrared wavelengths [4] .

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 21, 2021•0 citations

Improved slow light performances using photorefractive two-wave mixing

Nacera Bouldja, Marc Sciamanna, Delphine Wolfersberger

We experimentally observe an ultralow effective group velocity of 0.9 cm/s of light pulses using the two-wave mixing process in an Sn2P2S6 (SPS):Te crystal at a visible wavelength. The time delay can be controlled through the nonlinear photorefractive gain and the input pulse duration. By optimizing the nonlinearity strength, we achieve a maximum fractional delay of 0.79 for a pulse duration of 100 ms. Our photorefractive slow light system allows combining low group velocity with large delay-bandwidth product for pulse durations spanning three orders of magnitude.

Optics Letters•Mar 13, 2019•12 citations

Photorefractive manipulation of light pulses

Boris I. Sturman, Evgeniy V. Podivilov, M. V. Gorkunov

We investigate theoretically the main elements of manipulation of light pulses---strong nonlinear slowing down, trapping, and release on demand---in photorefractive nonlinear media. This includes a study of the slowing-down characteristics, such as delay time, amplification factor, and nonlinear broadening, for different types of photorefractive response and interaction geometries, as well as an analysis of the shape of pulses released after a long storage. The photorefractive manipulation method is shown to be applicable at ambient temperatures, low light intensities, and wide spectral ranges.

Physical Review A•Jun 9, 2008•9 citations
We study theoretically the effects of pulse slowdown and speedup in ferroelectric Sn2P2S6 possessing a self-compensating photorefractive response. It is shown that both these effects can be implemented in one sample for sufficiently large values of the coupling strength. In contrast to other types of the photorefractive response (local and nonlocal), the output pulses do not suffer from strong spatial amplification and broadening.
It has been shown recently (see, e.g., Nature, 397, 594, 1999; 409, 490, 2001) that light pulses can be remarkably slowed down in resonant gases under very low temperatures. We show theoretically and experimentally that a similar in nature (and stronger in value) phenomenon occurs in photorefractive nonlinear media. The pulse-maximum velocity can be reduced here to the value of thickness/response time because of the two wave coupling effect. Specific properties of pulse propagation depend on the type of the photorefractive response and also duration and shape of the input pulse. Our theoretical results for the nonlocal nonlinear response are in a good agreement with experimental data obtained with BaTiO3 and Sn2P2S6 crystals.
We theoretically study the effect of light deceleration in photorefractive nonlinear media. This includes consideration of different types of the photorefractive nonlinear response, different wave interaction schemes, and an analysis of the influence of the input parameters, such as the input temporal pulse width and the coupling strength, on the output pulse characteristics: the time delay, the propagation velocity, the amplification factor, and the output width. We show that photorefractive light deceleration has numerous advantages over other known techniques. It works already at low intensities, at room temperature, and within wide spectral ranges and offers a vast variety of handles for manipulating light pulses. An analogy with the light deceleration method based on the quantum effect of electromagnetically induced transparency in ultracold resonant gases is also considered.
Light pulse group velocity manipulations due to the specific dispersion of a medium (so-called “slow” and “fast” light phenomena) can be obtained on the basis of several mechanisms. One of these techniques is two-wave mixing in a photorefractive crystal. This work presents a modification of this method, exploiting the strong beam fanning in Sb-doped Sn2P2S6 crystals. Our experimental results demonstrate a “fast light” behavior of Gaussian pulses transmitted through a Sn2P2S6:Sb sample. The phenomenon is due to the beam fanning (i.e., the self-diffraction of the incident beam on self-induced noisy photorefractive gratings) that ensures a significant depletion of the input beam. Due to the relatively fast photorefractive response of the Sn2P2S6:Sb crystals this depletion occurs with times in the range of 10–100 ms, depending on the beam intensity, and the “fast light” feature is observed. The temporal and amplitude characteristics of the output beam are measured in function of the intensity and polarization azimuth of the incident beam. Besides, a negative phase shift of the periodical output beam relative to a sinusoidal intensity-modulated input beam is also obtained experimentally. It is shown that the phase and amplitude relation between the input and output periodic signals are described by a simple analytical expression that takes into account the beam fanning strength (depletion factor) and its dynamics (depletion time constant). It is also demonstrated that the pulse advance (or phase shift of the modulated signal) can be regulated by the light polarization azimuth. The advantages of the proposed method are discussed.
Recently, several works have shown that the light group velocity can be reduced using the recording of dynamic refractive index gratings in photorefractive (PR) crystals [1] , [2] , [3] . The slowdown of light is performed using optical beams wave mixing: it yields the output pulse amplification and increases the light dispersion inside the PR crystal. For example, the TWM method demonstrated that the delay time ∆ τ can be varied as a function of the TWM gain values Γ and the input pulse widths T 0 . However, several works have shown that the results achieved by this method are limited in terms of pulse duration. Indeed, only long pulses with time duration of ms−s can be slowdown in a PR crystal both at the visible and the infrared wavelengths [4] .
We experimentally observe an ultralow effective group velocity of 0.9 cm/s of light pulses using the two-wave mixing process in an Sn2P2S6 (SPS):Te crystal at a visible wavelength. The time delay can be controlled through the nonlinear photorefractive gain and the input pulse duration. By optimizing the nonlinearity strength, we achieve a maximum fractional delay of 0.79 for a pulse duration of 100 ms. Our photorefractive slow light system allows combining low group velocity with large delay-bandwidth product for pulse durations spanning three orders of magnitude.
We investigate theoretically the main elements of manipulation of light pulses---strong nonlinear slowing down, trapping, and release on demand---in photorefractive nonlinear media. This includes a study of the slowing-down characteristics, such as delay time, amplification factor, and nonlinear broadening, for different types of photorefractive response and interaction geometries, as well as an analysis of the shape of pulses released after a long storage. The photorefractive manipulation method is shown to be applicable at ambient temperatures, low light intensities, and wide spectral ranges.