Journal of Nonlinear Optical Physics & Materials 

About: Journal of Nonlinear Optical Physics & Materials is an academic journal published by World Scientific. The journal publishes majorly in the area(s): Laser & Nonlinear system. It has an ISSN identifier of 0218-8635. Over the lifetime, 1364 publications have been published receiving 10437 citations. The journal is also known as: Journal of nonlinear optical physics and materials & International journal of nonlinear optical physics.

Single-Beam Z-Scan: Measurement Techniques and Analysis

Abstract: The Z-scan technique is a popular method for measuring degenerate (single frequency) optical nonlinearities using a single laser beam. In order to perform reliable measurements, it is necessary to carefully characterize and control a number of experimental parameters, such as the beam quality, the power and temporal characteristics of the laser, the collection aperture size and position, the sample reflectivity, sample thickness and imperfections in the sample. Failure to control these parameters leads to inaccurate determinations of the nonlinearities. In this paper, we review the theory of Z-scan and examine each of these issues from experimental and theoretical viewpoints. This work will be of interest to anyone who performs Z-scan experiments and to those interested in optical power limiting and nonlinear optical propagation.

Quasi-Phasematched Nonlinear Interactions and Devices

Abstract: The field of nonlinear optics began nearly simultaneously in the United States and in Russia in 1962. The early years of discovery led to an understanding of nonlinearity in materials, phasematching, and nonlinear device performance. In the second decade of the 1970s, tunable parametric oscillators driven by high-peak-power Q-switched lasers made the transition to tools useful for spectroscopy and remote sensing. In the late 1980s engineered nonlinear materials were introduced with the successful implementation of quasi-phasematching by periodic inversion of ferroelectric domains in lithium niobate. Lithographic processing techniques enabled the fabrication of quasi-phasematched nonlinear "chips" using electric field poling of lithium niobate at the wafer scale.

Plasmon modes in metal nanowires and left-handed materials

Abstract: The electromagnetic eld distribution for thin metal nanowires is found, by using the discrete dipole approximation. The plasmon polariton modes in wires are numerically simulated. These modes are found to be dependent on the incident light wavelength and direction of propagation. The existence of localized plasmon modes and strong local eld enhancement in percolation nanowire composites is demonstrated. Novel left-handed materials in the near-infrared and visible are proposed based on nanowire composites.

Electro-optical switching characteristics of volume holograms in polymer dispersed liquid crystals

Abstract: Electrically switchable volume holograms lead to the possiblity of real-time electro-optical control of diffractive optic components. We report here on the development of a novel photopolymer-liquid crystal composite material system for writing in a fast single step, high diffraction efficiency volume holograms, capable of switching in applied electric fields of low voltage. Switching of a first-order Bragg diffracted beam into the zero-order with an applied field of ~10 V/µm was observed. With the addition of a surfactant to our pre-polymer syrup, we observed lowering of the switching fields to ~5 V/µm. We report response times for switching and relaxation in the order of microseconds. Low voltage, high resolution scanning electron microscopy studies show that the Bragg gratings formed consist of periodic polymer dispersed liquid crystal planes. The addition of surfactant leads to formation of very uniform small (20–40 nm) nematic droplets. A simple model based on the shape of the liquid crystal droplets...

Filamentation and supercontinuum generation during the propagation of powerful ultrashort laser pulses in optical media (white light laser)

Abstract: The fundamental physical mechanism responsible for the self-focussing, filamentation, supercontinuum generation and conical emission of a powerful ultrashort laser pulse in a transparent optical medium is reviewed. The propagation can be described by the model of moving focus modified by the defocussing effect of the self-induced plasma through multiphoton interaction with the medium. Spatial and temporal self-phase modulation in both the neutral Kerr medium and the plasma transform the pulse into a chirped (elongated) and strongly deformed pulse both temporally and spatially. The manifestation of the deformation is supercontinuum generation and conical emission. A new phenomenon of refocussing was observed. It is due to the diffraction of the trailing part of the pulse by the plasma that results in a ring structure of positive index changes surrounding the plasma column. This ring structure refocuses the pulse partially. The measured coherence lengths of the various frequencies components of the supercontinuum are independent of the optical media used and are essentially equal to that of the pump laser pulse when compared to an incoherent white light source. We thus justify that such a deformed pulse with a very broad spectrum could be called a chirped white light laser pulse.