Results 261 to 270 of about 17,683 (311)

Control of optical turbulence

2007 European Conference on Lasers and Electro-Optics and the International Quantum Electronics Conference, 2007
We consider the suppression of the so-called "turbulent regimes" in optical systems with advection. It is well known that spatiotemporal systems submitted to advection can undergo a convective instability above a critical value of the drift parameter.
C. Evain, C. Szwaj, S. Bielawski, M. Hosaka, Y. Takashima, A. Mochihashi, M. Katoh, M.E. Couprie   +7 more
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Trajectory of an optical vortex in atmospheric turbulence

Physical Review E, 2009
Trajectory of an optical vortex has been identified for its propagation in atmospheric turbulence using numerical simulations. An analytical expression has been found, relating the radial departure of the vortex in plane perpendicular to the direction of propagation, to the refractive index structure function parameter and the inner scale of turbulence.
Dipankar, A., Marchiano, R., Sagaut, P.
openaire   +2 more sources

Weak Optical Turbulence in Class-A Nonlinear Optical Systems

EQEC'96. 1996 European Quantum Electronic Conference, 1996
Transverse pattern formation and weak optical turbulence is theoretically investigated in multi-transverse-mode class-A nonlinear optical systems (primarily class-A lasers). It is shown, that "nontrivial patterns" occur due to transverse mode locking to a common frequency in class-A nonlinear optical systems.
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Wander of an optical beam in the turbulent atmosphere

Applied Optics, 1990
A simple, analytic, geometrical optics expression for the variance of the beam displacements caused by propagation through weak refractive turbulence described by the Kolmogorov spectrum is presented. The analytical formula includes the effect of the divergence or convergence of the initial beam.
J H, Churnside, R J, Lataitis
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An optical study of turbulence

Journal of Fluid Mechanics, 1970
This paper describes theoretical and experimental work carried out at the Cavendish Laboratory of the University of Cambridge. The main object of the work was to develop a new technique for measuring the structure of fluid turbulence.A parallel beam of light is passed through the turbulent region, containing refractive index fluctuations, and analyzed ...
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Synthesis of anisotropic optical turbulence at the laboratory

Optics Letters, 2016
At the foundation of the problem of light propagation through optical turbulence is the classical Obukhov-Kolmogorov theory. It rests in the requirement that the refractive index fluctuations should be homogeneous and isotropic. These, with other necessary assumptions, lead to the very well-known -11/3-power exponent spectrum on the inertial range ...
Gustavo, Funes, Felipe, Olivares, Camilo G, Weinberger, Yeraldinne D, Carrasco, Leandro, Nuñez, Darío G, Pérez   +5 more
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Optical properties of turbulent channel flow

Applied Optics, 1990
We have measured the scaling behavior of the turbulent scattering of a beam transmitted through a heated channel flow and conclude that the use of He in a properly engineered channel allows for efficient operation of gas cooled disk amplifiers at average power.
G F, Albrecht, H F, Robey, A C, Erlandson   +2 more
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Optical propagation in laboratory-generated turbulence

Applied Optics, 1979
A versatile and useful facility for simulating the effects of atmospheric turbulence on optical propagation is described, and the relevant system parameters are characterized. The scattering medium is a turbulent liquid (ethanol) with the turbulence created by unstable convection generated by a strong vertical thermal gradient.
R A, Elliott, J R, Kerr, P A, Pincus
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Optical properties of a planar turbulent jet

Applied Optics, 1995
A planar heated air jet was constructed. Its flow properties were characterized and shown to be both reproducible and in good agreement with the results of turbulence theory. The optical properties of the jet were studied with the help of a 632.8-nm He-Ne laser beam.
I A, Joia, R J, Perkins, B J, Uscinski, G, Balmer, D, Jordan, E, Jakeman   +5 more
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Turbulent Transitions in Optical Wave Propagation

Physical Review Letters, 2016
We report the direct observation of the onset of turbulence in propagating one-dimensional optical waves. The transition occurs as the disordered hosting material passes from being linear to one with extreme nonlinearity. As the response grows, increased wave interaction causes a modulational unstable quasihomogeneous flow to be superseded by a chaotic
PIERANGELI, DAVIDE, DI MEI , FABRIZIO, DI DOMENICO, GIUSEPPE, Agranat, A. J., CONTI, CLAUDIO, DEL RE, EUGENIO   +5 more
openaire   +5 more sources