Frequency response and tunability of grating-assisted directional couplers

The spectral properties of grating-assisted directional couplers are studied using an improved coupled mode formulation. Key parameters for the design of these structures, such as the grating period, the coupling length, and other structural parameters, are calculated. The frequency response, the filter bandwidth, and the tuning range are analyzed. The technique is used to examine a specific case of InGaAsP-InP tunable filters, and the results are compared to a prior experimen

Frequency control using a complex effective reflectivity in laterally coupled semiconductor laser arrays

Frequency selectivity of a novel type of multielement, multisection laterally coupled semiconductor laser array is studied using the round-trip method. It is found that such a structure should lead to a strong frequency selectivity owing to a periodic dependency of the threshold gain on the frequency. A gain-guided two-coupled-cavity device was fabricated. The experimental results show excellent agreement with the theoretical prediction

Computer based library management

Cover title"1789"--handwritten on cover. -- Series statement handwritten on coverIncludes bibliographical reference

ADMINS : a progress report

"1688"--handwritten on cover"January 1967.

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http://www.ester.ee/record=b4483013*es

Enhanced coupling to microsphere resonances with optical fibers

Cataloged from PDF version of article.Morphology-dependent resonances (MDR's) of polystyrene microspheres were excited by an optical fiber coupler. For optical elimination of the air-cladding interface at the optical fiber coupler surface, the microsphere was immersed in an index-matching oil. MDR's were observed, even though the relative refractive index between the microsphere and the oil was only 1.09. The observed MDR spectra are in good agreement with the generalized Lorenz-Mie theory and the localization principle. The scattering efficiency into each MDR is estimated as a function of the impact parameter by means of generalized Lorenz-Mie theory. (C) 1997 Optical Society of America