Ultrashort pulses propagation through different approaches of the Split-Step Fourier method

Simulating the propagation of optical pulses in a single mode optical fiber is of fundamental importance for studying the several effects that may occur within such medium when it is under some linear and nonlinear effects. In this work, we simulate it by implementing the nonlinear Schrödinger equation using the Split-Step Fourier method in some of its approaches. Then, we compare their running time, algorithm complexity and accuracy regarding energy conservation of the optical pulse. We note that the method is simple to implement and presents good results of energy conservation, besides low temporal cost. We observe a greater precision for the symmetrized approach, although its running time can be up to 126% higher than the other approaches, depending on the parameters set. We conclude that the time window must be adjusted for each length of propagation in the fiber, so that the error regarding energy conservation during propagation can be reduced.

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A single-shot third-order autocorrelator for pulse contrast and pulse shape measurements

Laser and Particle Beams ◽

10.1017/s0263034601192116 ◽

2001 ◽

Vol 19 (2) ◽

pp. 231-235 ◽

Cited By ~ 28

Author(s):

J. COLLIER ◽

C. HERNANDEZ-GOMEZ ◽

R. ALLOTT ◽

C. DANSON ◽

A. HALL

Keyword(s):

Pulse Shape ◽

Optical Pulse ◽

Dynamic Range ◽

Time Window ◽

Ultrashort Pulses ◽

Fixed Time ◽

Second Order ◽

Single Shot ◽

Third Order ◽

Pulse Contrast

We present the design of a single-shot third-order autocorrelator that can be used to measure optical pulse lengths of ultrashort pulses within a fixed time window on a single-shot basis. It has a number of advantages over traditional second-order autocorrelation devices, namely a more direct and accurate measurement of pulse shape, the ability to differentiate temporal activity ahead and behind the pulse, and an increased dynamic range. The design is linear and is, in principle, no more difficult to construct and operate than a second-order autocorrelator.

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Amplification characteristics in active tapered segmented cladding fiber with large mode area

High Power Laser Science and Engineering ◽

10.1017/hpl.2021.20 ◽

2021 ◽

Vol 9 ◽

Author(s):

Caijian Xie ◽

Tigang Ning ◽

Jingjing Zheng ◽

Li Pei ◽

Jianshuai Wang ◽

...

Keyword(s):

High Power ◽

Heat Load ◽

Nonlinear Effects ◽

Single Mode ◽

Large Mode Area ◽

High Loss ◽

Effective Mode Area ◽

Steady State Rate ◽

State Rate ◽

Mode Area

Abstract A kind of tapered segmented cladding fiber (T-SCF) with large mode area (LMA) is proposed, and the mode and amplification characteristics of T-SCFs with concave, linear, and convex tapered structures are investigated based on finite-element method (FEM) and few-mode steady-state rate equation. Simulation results indicate that the concave tapered structure can introduce high loss for high-order modes (HOMs) that is advantageous to achieve single-mode operation, whereas the convex tapered structure provides large effective mode area that can help to mitigate nonlinear effects. Meanwhile, the small-to-large amplification scheme shows further advantages on stripping off HOMs, and the large-to-small amplification scheme decreases the heat load density induced by the high-power pump. Moreover, single-mode propagation performance, effective mode area, and heat load density of the T-SCF are superior to those of tapered step index fiber (T-SIF). These theoretical model and numerical results can provide instructive suggestions for designing high-power fiber lasers and amplifiers.

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Second Order Averaging Study of an Autoparametric System

14th Biennial Conference on Mechanical Vibration and Noise: Nonlinear Vibrations ◽

10.1115/detc1993-0038 ◽

1993 ◽

Author(s):

Bappaditya Banerjee ◽

Anil K. Bajaj ◽

Patricia Davies

Keyword(s):

Dynamical Behavior ◽

Period Doubling ◽

Nonlinear Effects ◽

Single Mode ◽

Pitchfork Bifurcation ◽

Second Order ◽

System Response ◽

Response Curves ◽

Vibratory System ◽

First Order

Abstract The autoparametric vibratory system consisting of a primary spring-mass-dashpot system coupled with a damped simple pendulum serves as an useful example of two degree-of-freedom nonlinear systems that exhibit complex dynamic behavior. It exhibits 1:2 internal resonance and amplitude modulated chaos under harmonic forcing conditions. First-order averaging studies of this system using AUTO and KAOS have yielded useful information about the amplitude dynamics of this system. Response curves of the system indicate saturation and the pitchfork bifurcation sets are found to be symmetric. The period-doubling route to chaotic solutions is observed. However questions about the range of the small parameter ε (a function of the forcing amplitude) for which the solutions are valid cannot be answered by a first-order study. Some observed dynamical behavior, like saturation, may not persist when higher-order nonlinear effects are taken into account. Second-order averaging of the system, using Mathematica (Maeder, 1991; Wolfram, 1991) is undertaken to address these questions. Loss of saturation is observed in the steady-state amplitude responses. The breaking of symmetry in the various bifurcation sets becomes apparent as a consequence of ε appearing in the averaged equations. The dynamics of the system is found to be very sensitive to damping, with extremely complicated behavior arising for low values of damping. For large ε second-order averaging predicts additional Pitchfork and Hopf bifurcation points in the single-mode response.

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Fourier‐transform‐limited, single‐mode picosecond optical pulse generation by a distributed feedback InGaAsP diode laser

Applied Physics Letters ◽

10.1063/1.95421 ◽

1984 ◽

Vol 45 (8) ◽

pp. 843-845 ◽

Cited By ~ 9

Author(s):

Noriaki Onodera ◽

Hiromasa Ito ◽

Humio Inaba

Keyword(s):

Fourier Transform ◽

Diode Laser ◽

Optical Pulse ◽

Single Mode ◽

Pulse Generation ◽

Distributed Feedback ◽

Optical Pulse Generation

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COMPRESSION OF BRIGHT OPTICAL PULSE BY PULSE PAIR IN THE NORMAL DISPERSION REGIME OF SINGLE MODE FIBERS

Acta Physica Sinica ◽

10.7498/aps.46.919 ◽

1997 ◽

Vol 46 (5) ◽

pp. 919

Author(s):

CAO WEN-HUA ◽

ZHANG YOU-WEI ◽

LIU SONG-HAO ◽

GUO QI ◽

XU WEN-CHENG

Keyword(s):

Optical Pulse ◽

Single Mode ◽

Normal Dispersion ◽

Pulse Pair ◽

Dispersion Regime

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Extremely short optical pulses and superstrings

Modern Physics Letters A ◽

10.1142/s0217732320502211 ◽

2020 ◽

Vol 35 (27) ◽

pp. 2050221

Author(s):

Mikhail B. Belonenko ◽

Natalia N. Konobeeva ◽

Alexander V. Zhukov

Keyword(s):

Numerical Solution ◽

Effective Action ◽

Optical Pulse ◽

Optical Pulses ◽

Maxwell’S Equation ◽

Pulse Dynamics ◽

Short Optical Pulse ◽

Time Space ◽

Extremely Short Optical Pulses ◽

Schwinger Mechanism

We analyze the propagation of an extremely short optical pulse from the numerical solution of the Maxwell’s equation related to the effective action obtained in the framework of the theory of superstrings in flat time space. The pulse dynamics turned out to be unstable and eventually leads to a collapse. We particularly analyze the Schwinger mechanism which occurs during the collapse of the pulse.

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