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

Comprehensive study on the concept of temporal optical waveguides

Junhe Zhou, Guozeng Zheng, Jianjie Wu

Published Jun 27, 2016• 25 citations
Publisher

Abstract

Time and space are dual variables which bring a lot of analogies during theoretical study. In this paper, we extend the concept of a spatial optical waveguide to the temporal domain. Here we show that it is possible to confine the optical pulse within a time interval by introducing the temporal index boundaries. The confined pulse will propagate at a speed of the index change in the waveguide, and it will be behind the original optical pulse which propagates without the temporal index variations. In this way, we may offer an approach to broaden the bandwidth of the slow light and to tune the light speed based on the existing slow light devices. The temporal waveguide has modes, which are the temporal waveforms maintaining their shapes during the propagation. In a single-mode temporal waveguide, the pulse retains its shape as the only mode of the waveguide just like an optical soliton. In a multimode temporal waveguide, multimode interference effect exists, which can duplicate a single pulse into multiple copies and be potentially implemented for all-optical signal processing.

DOI
10.1103/physreva.93.063847

Related papers

Light stopping by reflection from a moving index front

Mahmoud Gaafar, Jannik Holtorf, Manfred Eich +1 more

Nonlinearly generated refractive index fronts in waveguides can change the signal frequency and wavenumber leading to the indirect transitions. Here, we discuss how dynamic light stopping and pulse time reversal can be implemented in dispersive waveguides via these transitions. Our scheme, in contrast to previous concepts of light stopping and time reversal, is not limited by a strict phase matching condition and does not require local index variations, thus, can manipulate broadband signals in a single step process. The presented results are experimentally feasible using existing photonic waveguides technologies.

Conference on Lasers and Electro-Optics•Jan 1, 2021•0 citations

Dynamic Light Storage in Slow Light Waveguides

Michel Castellanos Muñoz, Adarsha Kanchana, Alexander Yu. Petrov +1 more

An approach to store light dynamically in slow light waveguides is proposed. First, design guidelines are developed for waveguides that allow dynamic group velocity control. Then an example of a silicon photonic crystal waveguide is presented where group velocity can be drastically reduced by applying a refractive index change of${-}{5.5}\times 10^{-2}$to a specific part of the waveguide. Performing the index change while a light pulse is confined to the waveguide, we show by numerical simulations a tunable storage time of more than 70 ps for a pulse of 60 GHz bandwidth. We argue that the magnitude of the required change of the refractive index can be reduced by mode optimization.

IEEE Journal of Quantum Electronics•Apr 11, 2012•5 citations

Front induced transitions: refractive index fronts in dispersive waveguides

Mahmoud Gaafar, Hagen Renner, Toshihiko Baba +2 more

Moving refractive index fronts in waveguides with dispersion is a special type of spatio-temporal modulation leading to the change of signal frequency and wavenumber. The interaction of light with such fronts allows frequency conversion, light stopping, optical delays as well as bandwidth and pulse duration manipulation. We will present theoretical and experimental examples of signal transmission, reflection and trapping by the front and highlight special situations such as light stopping, time reversal or optical push broom effect. We will geometrically consider indirect transitions in the dispersion relation using the phase continuity relation at the front and present numerical solutions of the linear Schrödinger equation which follows from the slowly varying envelope approximation of the wave equation. In particular, for highly dispersive waveguides a temporal evolution of the spatial wave envelopes are considered in contrast to conventional spatial evolution of temporal envelopes. Further, we will present an overview of experimental results and estimate the maximal achievable effects for each of the application in different waveguide systems.

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

Pulse time reversal and stopping by a refractive index front

Mahmoud Gaafar, Jannik Holtorf, Manfred Eich +1 more

We discuss how dynamic light stopping and pulse time reversal can be implemented in dispersive waveguides via indirect photonic transitions induced by moving refractive index fronts. The previous concepts of light stopping/time reversal either require complex local variation of the device’s refractive index or rely on the strict phase matching condition, which imposes limitations on the amount of manipulated information. Until now, only single pulses or continuous waves were manipulated experimentally. Our scheme is not limited by a strict phase matching condition and does not require local index variations, thus it can manipulate broadband signals in a single step process. Here, we present several numerically integrated results for pulse time reversal and stopping/storage via indirect front-induced transitions. The presented results are experimentally feasible using existing photonic waveguide technologies.

APL Photonics•Aug 1, 2020•12 citations

Soliton signals propagating in fiber waveguides and slow light generation

Iraj Sadegh Amiri, Abdolkarim Afroozeh, H. Ahmad

An optical fiber consists of a transparent core surrounded by a transparent cladding material with a lower refractive index. Fibers which can be used for many propagation paths or transverse modes are called Multi-Mode Fibers whereas those which can only support a single mode are called Single Mode Fiber. Optical solitons are localized as electromagnetic waves that propagate in nonlinear media resulting from a balance between nonlinearity and linear broadening due to dispersion and/or diffraction. Ring resonators are employed to generate signals used for optical communication applications, where they can be integrated in a single system. A PANDA ring resonator can be used to generate chaotic signals. Slow light refers to the control of the light velocity in a particular medium. Slow light techniques can be used for future optical communication systems, including optical buffering, data synchronization and optical memories.

CRC Press eBooks•Dec 8, 2016•0 citations

Slow light in photonic crystal waveguides

Thomas F. Krauss

The physical principles behind the phenomenon of slow light in photonic crystal waveguides, as well as their practical limitations, are discussed and put into context. This includes the nature of slow light propagation, its bandwidth limitation, the scaling of linear and nonlinear interactions with the slowdown factor as well as issues such as losses, coupling into and the tuning of slow modes. Applications in all-optical signal processing appear to be the most promising outcome of the phenomena discussed.

Journal of Physics D Applied Physics•Apr 19, 2007•664 citations
Time and space are dual variables which bring a lot of analogies during theoretical study. In this paper, we extend the concept of a spatial optical waveguide to the temporal domain. Here we show that it is possible to confine the optical pulse within a time interval by introducing the temporal index boundaries. The confined pulse will propagate at a speed of the index change in the waveguide, and it will be behind the original optical pulse which propagates without the temporal index variations. In this way, we may offer an approach to broaden the bandwidth of the slow light and to tune the light speed based on the existing slow light devices. The temporal waveguide has modes, which are the temporal waveforms maintaining their shapes during the propagation. In a single-mode temporal waveguide, the pulse retains its shape as the only mode of the waveguide just like an optical soliton. In a multimode temporal waveguide, multimode interference effect exists, which can duplicate a single pulse into multiple copies and be potentially implemented for all-optical signal processing.
Nonlinearly generated refractive index fronts in waveguides can change the signal frequency and wavenumber leading to the indirect transitions. Here, we discuss how dynamic light stopping and pulse time reversal can be implemented in dispersive waveguides via these transitions. Our scheme, in contrast to previous concepts of light stopping and time reversal, is not limited by a strict phase matching condition and does not require local index variations, thus, can manipulate broadband signals in a single step process. The presented results are experimentally feasible using existing photonic waveguides technologies.
An approach to store light dynamically in slow light waveguides is proposed. First, design guidelines are developed for waveguides that allow dynamic group velocity control. Then an example of a silicon photonic crystal waveguide is presented where group velocity can be drastically reduced by applying a refractive index change of−5.5×10−2{-}{5.5}\times 10^{-2}−5.5×10−2to a specific part of the waveguide. Performing the index change while a light pulse is confined to the waveguide, we show by numerical simulations a tunable storage time of more than 70 ps for a pulse of 60 GHz bandwidth. We argue that the magnitude of the required change of the refractive index can be reduced by mode optimization.
Moving refractive index fronts in waveguides with dispersion is a special type of spatio-temporal modulation leading to the change of signal frequency and wavenumber. The interaction of light with such fronts allows frequency conversion, light stopping, optical delays as well as bandwidth and pulse duration manipulation. We will present theoretical and experimental examples of signal transmission, reflection and trapping by the front and highlight special situations such as light stopping, time reversal or optical push broom effect. We will geometrically consider indirect transitions in the dispersion relation using the phase continuity relation at the front and present numerical solutions of the linear Schrödinger equation which follows from the slowly varying envelope approximation of the wave equation. In particular, for highly dispersive waveguides a temporal evolution of the spatial wave envelopes are considered in contrast to conventional spatial evolution of temporal envelopes. Further, we will present an overview of experimental results and estimate the maximal achievable effects for each of the application in different waveguide systems.
We discuss how dynamic light stopping and pulse time reversal can be implemented in dispersive waveguides via indirect photonic transitions induced by moving refractive index fronts. The previous concepts of light stopping/time reversal either require complex local variation of the device’s refractive index or rely on the strict phase matching condition, which imposes limitations on the amount of manipulated information. Until now, only single pulses or continuous waves were manipulated experimentally. Our scheme is not limited by a strict phase matching condition and does not require local index variations, thus it can manipulate broadband signals in a single step process. Here, we present several numerically integrated results for pulse time reversal and stopping/storage via indirect front-induced transitions. The presented results are experimentally feasible using existing photonic waveguide technologies.
An optical fiber consists of a transparent core surrounded by a transparent cladding material with a lower refractive index. Fibers which can be used for many propagation paths or transverse modes are called Multi-Mode Fibers whereas those which can only support a single mode are called Single Mode Fiber. Optical solitons are localized as electromagnetic waves that propagate in nonlinear media resulting from a balance between nonlinearity and linear broadening due to dispersion and/or diffraction. Ring resonators are employed to generate signals used for optical communication applications, where they can be integrated in a single system. A PANDA ring resonator can be used to generate chaotic signals. Slow light refers to the control of the light velocity in a particular medium. Slow light techniques can be used for future optical communication systems, including optical buffering, data synchronization and optical memories.
The physical principles behind the phenomenon of slow light in photonic crystal waveguides, as well as their practical limitations, are discussed and put into context. This includes the nature of slow light propagation, its bandwidth limitation, the scaling of linear and nonlinear interactions with the slowdown factor as well as issues such as losses, coupling into and the tuning of slow modes. Applications in all-optical signal processing appear to be the most promising outcome of the phenomena discussed.