Results 281 to 290 of about 532,284 (336)
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Dispersive pulse propagation and group velocity
The Journal of the Acoustical Society of America, 1993The propagation of pulses in a dissipative medium is investigated both theoretically and experimentally. The theoretical work is based on the dissipative dispersion integral, and the measurements are made in an air-filled periodic waveguide (i.e., the dispersion is Bloch wave dispersion).
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Group velocity dispersion manipulation in integrated waveguides
2013 Conference on Lasers & Electro-Optics Europe & International Quantum Electronics Conference CLEO EUROPE/IQEC, 2013The ability to arbitrarily control the chromatic dispersion in CMOS-compatible waveguides should strengthen the viability of this technology, particularly for nonlinear devices on a chip [1]. Here we report on a systematic investigation of group velocity dispersion engineering in channel and rib waveguides with a silicon nitride core (Si3N4).
J. M. Chavez Boggio +5 more
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Group-velocity dispersion in a Bragg fiber
Journal of the Optical Society of America B, 2008A comprehensive study of the group-velocity dispersion of the TE, TM, and hybrid modes in a Bragg fiber is presented by showing many numerical examples. The dispersion can be represented in a simple form as the sum of the material and the waveguide dispersions under the quarter-wave stack condition.
Jun-Ichi Sakai, Kazuki Kuramitsu
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Group velocity dispersion using commercial optical design programs
Applied Optics, 2003Three commercial optical design programs are used to model familiar geometries in ultrafast optics. A set of macros has been created to calculate the pulse delay, group velocity dispersion, and third-order dispersion caused by the components in an ultrafast optical system. The results correspond to published values.
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Dispersive ionization waves with constant group velocity
Physics Letters A, 1976Abstract Dispersive ionization waves with the linear dispersion relation are discussed. A coupling between the ordinary sound wave and the F - ionization wave is presented as a possible explanation of the straightening of the free F - ionization wave dispersion relation.
M. Chvojka, L. Pekárek, H. Urbánková
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Adjustable negative group-velocity dispersion in graded-index lenses
Optics Letters, 1992An analysis of group-velocity dispersion in graded-index (GRIN) lenses is presented. The analysis shows that continuously adjustable negative group-velocity dispersion up to hundreds of square femtoseconds can be produced by propagating the optical beam off the axis of a GRIN lens.
A C, Tien, R, Chang, J, Wang
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Two theorems for the group velocity in dispersive media
Physical Review A, 1993Two theorems on the group velocity are presented in this paper. First a simple proof is given that for any dispersive dielectric, there must be a frequency at which the group velocity of an electromagnetic pulse becomes abnormal, i.e., greater than the vacuum speed of light, infinite, or negative.
, Bolda, , Chiao, , Garrison
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Group velocity dispersion in depressed index type planar waveguides
Applied Optics, 1990Group velocity dispersion is calculated in weakly guiding slab guides having depressed index layer(s) next to the guiding region. Negative guide dispersion is easily obtained in the single mode regime. The amount of negative dispersion increases with index depth and physical width of the depressed index region.
A, Dienes, Y, Peng, A, Knoesen
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Group velocity and nonlinear dispersive wave propagation
Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences, 1973By the use of a Hamiltonian formulation, a basic group velocity is defined as the derivative of frequency with respect to wavenumber keeping action density constant, and is shown to represent an incremental action velocity in the general nonlinear case. The stability treatment of Whitham and Lighthill is extended to several dimensions. The
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OPTICAL FIBERS WITH NEGATIVE GROUP-VELOCITY DISPERSION IN THE VISIBLE
Optics News, 1988In 1978, Hill et al.1 observed that subjecting optical fibers to illumination with green light from an Ar+ ion laser for approximately ten minutes could establish a grating along the fiber core. Reflectivities as high as 90% were achieved, with a bandwidth of approximately 200 MHz.
C P, Kuo +4 more
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