Results 121 to 130 of about 24,405 (168)

Heterostructure as a nonlinear crystal

Physics Letters A, 1992
Abstract The motion of an electron in the potential well of a heterostructure is considered. The cubic susceptibility of electrons in such a system in the presence of an electromagnetic field is calculated. The nonlinearity of the electron motion in the electromagnetic field is explained by the nonparabolic dependence of the energy on the quasi ...
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Mode conversion in quadratic nonlinear crystals

Optics Letters, 2008
We propose a novel all-optical, nonlinear mode-conversion scheme based on cascaded three-wave-mixing phase-matched interactions in quadratic nonlinear crystals. We demonstrate the method experimentally by performing all-optical mode conversion of an input 1636 nm Hermite-Gaussian mode from the zeroth order to the first order using two periodically ...
Tal, Ellenbogen, Ido, Dolev, Ady, Arie
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Twisting Light by Nonlinear Photonic Crystals

Physical Review Letters, 2012
We report the observation of nonlinear interactions in quadratic nonlinear crystals having a geometrically twisted susceptibility pattern. The quasi-angular-momentum of these crystals is imprinted on the interacting photons during the nonlinear process so that the total angular momentum is conserved.
Noa Voloch, Bloch, Keren, Shemer, Asia, Shapira, Roy, Shiloh, Irit, Juwiler, Ady, Arie   +5 more
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Nonlinear Photonic Crystals

Physical Review Letters, 1998
Nonlinear frequency conversion in 2D ${\ensuremath{\chi}}^{(2)}$ photonic crystals is theoretically studied. Such a crystal has a 2D periodic nonlinear susceptibility, and a linear susceptibility which is a function of the frequency, but constant in space.
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Optical nonlinearities in lyotropic liquid crystals

Il Nuovo Cimento D, 1988
The existence of an optical nonlinearity of the Kerr-like type in a lyotropic liquid crystal is described in c.w. operation. The nonlinearity is found using the liquid crystal as a cladding material in a waveguide, or studying the interface properties between the liquid crystal and an ordinary glass.
BERTOLOTTI, Mario, FAZIO, Eugenio, A. Ferrari, A. Nesrullajev, SIBILIA, Concetta   +4 more
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Optical nonlinearities in a lyotropic liquid crystal

Optics Letters, 1987
The existence of an optical nonlinearity in a lyotropic liquid crystal has been demonstrated in an optical waveguide. A large hysteresis, of origin to be clarified, is found in the optical response in all mesophases of potassium capryllate.
M, Bertolotti, A, Ferrari, C, Sibilia, A, Alippi, A N, Nesrullajev   +4 more
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Beam shaping through a nonlinear crystal

2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, 2006
The conversion efficiency of nonlinear crystals is increased by shaping the intensity distribution of the laser beam. A diffractive optic to shape the Gaussian input beam into a top-hat intensity profile was fabricated and tested.
Todd Lizotte, Andrew Stockham, John Smith   +2 more
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Nonlinear Control of Crystallization

2002
In this chapter, we present two applications of the nonlinear control method proposed in Chapter 2 to continuous and batch crystallization systems. Low-dimensional approximations of the population balances are derived and used for nonlinear controller design.
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Nonlinear pattern selection in explosive crystallization

Physical Review Letters, 1988
It is shown analytically, in a suitable limit, that a sharp pattern-selection mechanism exists in driven explosive crystallization: after the onset of a morphological instability of the steady-state crystallization front, nonlinear effects cause the front to develop a spatial pattern with a definite wavelength.
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Helically twisted nonlinear photonic crystals

Optics Letters
Nonlinear photonic crystals with a helical structure in the second-order nonlinear coefficient (χ(2)) are fabricated using infrared femtosecond laser poling in ferroelectric Sr0.61Ba0.39Nb2O6 crystals. The quasi-orbital angular momentum of the helical χ(2) structure can be imprinted on the interacting photons during nonlinear optical processes ...
Chen Yu, Shan Liu, Tianxiang Xu, Ruwei Zhao, Yan Sheng   +4 more
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