321 research outputs found
An Input Output Study for The Omaha SMSA
This study is an extension and refinement of a previous report on the Omaha Standard Metropolitan Statistical Area (SMSA) by Perry P. Chang. The present study makes three major changes in Chang\u27s report, in that it obtains output and value added of industries in the Omaha area, exports and imports of the industries, certain income multipliers, forecasts of output in the Omaha area. for 1975 and 1990, and compares the three results with Chang\u27s
Phase Controlled All-Optical Switching In Rocking Filter Fibers
We demonstrate experimentally that all-optical switching of a strong beam can be controlled by the phase of a weak beam in a rocking rotator fiber
Coupled Nonlinear Schr\"{o}dinger equation and Toda equation (the Root of Integrability)
We consider the relation between the discrete coupled nonlinear
Schr\"{o}dinger equation and Toda equation. Introducing complex times we can
show the intergability of the discrete coupled nonlinear Schr\"{o}dinger
equation. In the same way we can show the integrability in coupled case of dark
and bright equations. Using this method we obtain several integrable equations.Comment: 11 pages, LateX, to apper in J. Phys. Soc. Jpn. Vol. 66, No
Control of the Onset of Filamentation in Condensed Media
Propagation of intense, ultrashort laser pulses through condensed media like
crystals of BaF and sapphire results in the formation of filaments. We
demonstrate that the onset of filamentation may be controlled by rotating the
plane of polarization of incident light. We directly visualize filamentation in
BaF_2 via six-photon absorption-induced fluorescence and, concomitantly, by
probing the spectral and spatial properties of white light that is generated.Comment: To appear in Phys. Rev.
Ultra-flat wideband single-pump Raman-enhanced parametric amplification
We experimentally optimize a single pump fiber optical parametric amplifier in terms of gain spectral bandwidth and gain variation (GV). We find that optimal performance is achieved with the pump tuned to the zero-dispersion wavelength of dispersion stable highly nonlinear fiber (HNLF). We demonstrate further improvement of parametric gain bandwidth and GV by decreasing the HNLF length. We discover that Raman and parametric gain spectra produced by the same pump may be merged together to enhance overall gain bandwidth, while keeping GV low. Consequently, we report an ultra-flat gain of 9.6±0.5 dB over a range of 111 nm (12.8 THz) on one side of the pump. Additionally, we demonstrate amplification of a 60 Gbit/s QPSK signal tuned over a portion of the available bandwidth with OSNR penalty less than 1 dB for Q2 below 14 dB
Suppression and Enhancement of Soliton Switching During Interaction in Periodically Twisted Birefringent Fiber
Soliton interaction in periodically twisted birefringent optical fibers has
been analysed analytically with refernce to soliton switching. For this purpose
we construct the exact general two-soliton solution of the associated coupled
system and investigate its asymptotic behaviour. Using the results of our
analytical approach we point out that the interaction can be used as a switch
to suppress or to enhance soliton switching dynamics, if one injects
multi-soliton as an input pulse in the periodically twisted birefringent fiber.Comment: 10 pages, 4 figures, Latex, submitted to Phys. Rev.
Quantum many-body simulations using Gaussian phase-space representations
Phase-space representations are of increasing importance as a viable and
successful means to study exponentially complex quantum many-body systems from
first principles. This review traces the background of these methods, starting
from the early work of Wigner, Glauber and Sudarshan. We focus on modern
phase-space approaches using non-classical phase-space representations. These
lead to the Gaussian representation, which unifies bosonic and fermionic
phase-space. Examples treated include quantum solitons in optical fibers,
colliding Bose-Einstein condensates, and strongly correlated fermions on
lattices.Comment: Short Review (10 pages); Corrected typo in eq (14); Added a few more
reference
Interaction of quasilocal harmonic modes and boson peak in glasses
The direct proportionality relation between the boson peak maximum in
glasses, , and the Ioffe-Regel crossover frequency for phonons,
, is established. For several investigated materials . At the frequency the mean free path of the
phonons becomes equal to their wavelength because of strong resonant
scattering on quasilocal harmonic oscillators. Above this frequency phonons
cease to exist. We prove that the established correlation between
and holds in the general case and is a direct consequence of
bilinear coupling of quasilocal oscillators with the strain field.Comment: RevTex, 4 pages, 1 figur
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