Optical soliton perturbation and conservation law with Kudryashov's refractive index having quadrupled power-law and dual form of generalized nonlocal nonlinearity

We study the formation and propagation of chirped elliptic and solitary waves in the cubic-quintic nonlinear Helmholtz equation. This system describes nonparaxial pulse propagation in a planar waveguide with Kerr-like and quintic nonlinearities along with spatial dispersion originating from the nonparaxial effect that becomes dominant when the conventional slowly varying envelope approximation fails. We first carry out the modulational instability (MI) analysis of a plane wave in this system by employing the linear stability analysis and investigate the influence of different physical parameters on the MI gain spectra. In particular, we show that the nonparaxial parameter suppresses the conventional MI gain spectrum and also leads to a nontrivial monotonic increase in the gain spectrum near the tails of the conventional MI band, a qualitatively distinct behavior from the standard nonlinear Schrodinger system. We then study the MI dynamics by direct numerical simulations, which demonstrate the production of ultrashort nonparaxial pulse trains with internal oscillations and slight distortions at the wings. Following the MI dynamics, we obtain exact elliptic and solitary wave solutions using the integration method by considering physically interesting chirped traveling wave ansatz. In particular, we show that the system features intriguing chirped antidark, bright, gray, and dark solitary waves depending upon the nature of nonlinearities. We also show that the chirping is inversely proportional to the intensity of the optical wave. In particular, the bright and dark solitary waves exhibit unusual chirping behavior, which will have applications in the nonlinear pulse compression process.

Cubic-quintic nonlinear Helmholtz equation: Modulational instability, chirped elliptic and solitary waves

Photonic-based qubits and integrated photonic circuits have enabled demonstrations of quantum information processing (QIP) that promises to transform the way in which we compute and communicate. To that end, sources of polarization-entangled photon pair states are an important enabling technology. However, such states are difficult to prepare in an integrated photonic circuit. Scalable semiconductor sources typically rely on nonlinear optical effects where polarization mode dispersion (PMD) degrades entanglement. Here, we directly generate polarization-entangled states in an AlGaAs waveguide, aided by the PMD and without any compensation steps. We perform quantum state tomography and report a raw concurrence as high as 0.91 ± 0.01 observed in a 1,100-nm-wide waveguide. The scheme allows direct Bell state generation with an observed maximum fidelity of 0.90 ± 0.01 from another (800-nm-wide) waveguide. Our demonstration paves the way for sources that allow for the implementation of polarization-encoded protocols in large-scale quantum photonic circuits.

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Polarization-entangled photon pair sources based on spontaneous four wave mixing assisted by polarization mode dispersion

This paper demonstrates an all-optical switching model system comprising a single pulsed pump beam at 355 nm and a CW He–Ne signal beam at 632.8 nm with 2-(2'-hydroxyphenyl)benzothiazole (HBT) in ethanol solution. The origins of the optical switching effect were discussed. By the study of nonlinear optical properties for HBT in ethanol solvent, this paper verified that the excited-state intramolecular proton transfer (ESIPT) effect of HBT and the thermal effect of solvent worked on quite different time scales and together induced the change of the refractive index of HBT solution, leading to the signal beam deflection. The results indicated that the HBT molecule could be an excellent candidate for high-speed and high-sensitive optical switching devices.

All-optical switching and nonlinear optical properties of HBT in ethanol solution

Using the optical fibers and ultrashort pulses, we can demonstrate highly functional optical control. We have succeeded in generation of low-noise, ultraflat, high-quality supercontinuum (SC). Recently, octave spanning high-quality SC is also generated. The carrier envelope offset frequency measurement and ultrahigh resolution optical coherence tomography are demonstrated using SC. We can also generate widely wavelength-tunable ultrashort soliton pulses using soliton self-frequency shift (SSFS). So far, several new techniques have been proposed and demonstrated using SSFS. The author has also discovered novel two-pulse trapping phenomena. The ultrafast all-optical switching is demonstrated using the pulse trapping techniques, and principles and characteristics are described.

Highly Functional All-Optical Control Using Ultrafast Nonlinear Effects in Optical Fibers

An ultrafast all-optical switching using pulse trapping by orthogonally polarized soliton pulse in birefringent fiber is investigated both experimentally and numerically. The signal pulse, which is polarized along the fast axis, is trapped by the control soliton pulse along the slow axis; they subsequently copropagate along the fiber. Their wavelengths are red-shifted by the soliton self-frequency shift. The trapped pulse is shaped as a sech2 ultrashort pulse. It is also amplified by the Raman gain of the control pulse. Temporal response of the pulse trapping is estimated as 250 fs for 150 fs signal pulses. Ultrafast all-optical switching is demonstrated for the 0.84 THz pulse train.

Ultrafast all optical switching using pulse trapping in birefringent fibers

Ultrafast all-optical switching by use of pulse trapping in birefringent optical fiber is demonstrated both experimentally and numerically. The wavelengths of the control soliton pulse and the trapped soliton pulse are shifted to satisfy the condition of group velocity matching. Furthermore, the energy of the trapped pulse is increased through Raman gain of the control pulse. Only a signal pulse in the pulse train with temporal separation of about 1.2 ps is successfully picked off. The repetition frequency corresponds to 0.83 THz. The spectrogram of the optical switching is directly observed using the X-FROG technique. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 158(3): 38–44, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20470

https://www.onlinelibrary.wiley.com/doi/pdf/10.1002/eej.20470

Ultrafast all‐optical switching using pulse trapping by ultrashort soliton pulse in birefringent optical fiber

Ultrafast all optical switching by use of pulse trapping in birefringent optical fiber is demonstrated both experimentally and numerically. The wavelength of the control soliton pulse and the trapped soliton pulse is shifted to satisfy the condition of group-velocity matching. Furthermore, the energy of trapped pulse is increased through Raman gain of control pulse. Only a signal pulse among three pulses with temporal separation of about 1.2 ps is successfully picked off. The repetition frequency corresponds to 0.83THz. The spectrogram of the optical switching is directly observed using the X-FROG technique.

Ultrafast All Optical Switching using Pulse Trapping by Ultrashort Soliton pulse in Birefringent Optical Fiber

0.83 THz ultrafast all optical switching in anomalous dispersion region is demonstrated experimentally using pulse trapping by orthogonally polarized 150 fs soliton pulse. The achievable fastest switching speed is also discussed numerically.

http://ieeexplore.ieee.org/iel5/10492/33247/01569722.pdf

Ultrafast All Optical Switching in Anomalous Dispersion Region Using Pulse Trapping in Birefringent Fiber

Pulse trapping by orthogonally polarized ultrashort soliton pulse in birefringent fiber is investigated both experimentally and numerically. Ultrafast all optical switching using pulse trapping in anomalous dispersion region is demonstrated for the first time.

Yosuke Ukai

Papers

Ultrafast all optical switching using pulse trapping in birefringent fibers

Ultrafast all‐optical switching using pulse trapping by ultrashort soliton pulse in birefringent optical fiber

Ultrafast All Optical Switching using Pulse Trapping by Ultrashort Soliton pulse in Birefringent Optical Fiber

Ultrafast All Optical Switching in Anomalous Dispersion Region Using Pulse Trapping in Birefringent Fiber

Ultrafast all optical switching using pulse trapping by orthogonally polarized ultrashort soliton pulse