We present a collocation method to obtain the approximate solution of Troesch's problem which arises in the confinement of a plasma column by radiation pressure and applied physics. By using the Christov rational functions and collocation points, this method transforms Troesch's problem into a system of nonlinear algebraic equations. The rate of convergence is shown to be exponential. The numer...

We apply the Pancharatnam-Berry phase approach to plasmonic metasurfaces loaded by highly nonlinear multiquantum-well substrates, establishing a platform to control the nonlinear wave front at will based on giant localized nonlinear effects. We apply this approach to design flat nonlinear metasurfaces for efficient second-harmonic radiation, including beam steering, focusing, and polarization m...

Scientists from the University of California, Los Angeles, Brookhaven National Laboratory, Stanford Linear Accelerator Center and Lawrence Livermore National Laboratory have demonstrated for the first time the feasibility of using nonlinear harmonic self-amplified spontaneous emission (SASE) free electron laser (FEL) radiation to produce coherent, femtosecond x-rays. Nonlinear harmonic radiatio...

Nonlinear bilateral filters (BF) deliver a fine blend of computational simplicity and blurfree denoising. However, little is known about their nature, noise-suppressing properties, and optimal choices of filter parameters. Our study is meant to fill this gap—explaining the underlying mechanism of bilateral filtering and providing the methodology for optimal filter selection. Practical applicati...

We analyze two nonlinear optofluidic processes where nonlinearity is induced by the interplay between optical field and liquid interface. Specifically, guided optical waves generate radiation pressure on the liquid interface, which can in turn distort the liquid interface and modify the properties of the optical field. In the first example, we discuss the feasibility of nonlinear optofluidic so...

We report on a particularly strong third-order nonlinear response from nanostructured gold surfaces. Two incident laser beams with frequencies omega{1} and omega{2} give rise to four-wave mixing (4WM) fields with frequencies 2omega{1}-omega{2} and 2omega{2}-omega{1}. We demonstrate that the nonlinear response can be purely evanescent and that nanostructured surfaces convert the evanescent energ...

Stimulated Raman scattering of an ultraintense laser pulse in plasmas is studied by perturbatively including the leading order term of the Landau-Lifshitz radiation reaction force in the equation of motion for plasma electrons. In this approximation, the radiation reaction force causes a phase shift in nonlinear current densities that drive the two Raman sidebands (anti-Stokes and Stokes waves)...

We present the results of the first reduced model simulations of the nonlinear development of the two-plasmon decay instability in an inhomogeneous plasma, including properties of the 3/2 harmonic emission. A sharp increase in radiation and Langmuir turbulence fluctuation levels occurs above a threshold laser intensity that depends on initial fluctuation levels. We study the competition between...

Some Areas of Ramsar, a city in northern Iran are among the world’s wellknown inhabited areas with highest levels of natural radiation. Annual exposure levels in these areas are up to 260 mGy y‐1 and the mean exposure rate is about 10 mGy y‐1 for a population of about 2000 residents. If elevated levels of natural radiation as high as a few hundred mSv per year is detrimental to health and...

Coherent anti-Stokes Raman scattering (CARS) processes are "coherent," but the phase of the anti-Stokes radiation is lost by most incoherent spectroscopic CARS measurements. We propose a Raman microscopy imaging method called nonlinear interferometric vibrational imaging, which measures Raman spectra by obtaining the temporal anti-Stokes signal through nonlinear interferometry. With a more comp...