Alan R. Kost

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The modeling, design, simulation, fabrication, calibration, and testing of a three-element, 15.3 cm fiber Bragg grating strain sensor array with the coherent optical frequency domain reflectometry (C-OFDR) interrogation technique are demonstrated. The fiber Bragg grating array (FBGA) is initially simulated using in-house software that incorporates transfer(More)
We examine the photophysics of a colloidal suspension of C(60) particles in a micellar solution of Triton X-100 and water, prepared via a new synthesis which allows high-concentration suspensions. The particle sizes are characterized by transmission electron microscopy and dynamic light scattering and found to be somewhat polydisperse in the range of 10-100(More)
An arrayed waveguide grating (AWG) with a novel S-shaped design for broadband operation is demonstrated for the first time with III-V semiconductors. This device design provided a polarization and temperature insensitive operation. It is also shown that, despite the wide operating range, chromatic dispersion does not degrade the performance of the AWG. The(More)
We describe the origin of spectral modal noise in a fiber-coupled spectrograph. Prior investigations of this phenomenon have considered optical fibers with large cores that support thousands of optical modes and used a statistical treatment to analyze spectral noise that arises from interference between the modes. We examine spectral modal noise for a(More)
We demonstrate optical limiting for the C(60) fullerene in polymethyl methacrylate (PMMA) as a solid polymer host. It is shown that the optical-limiting behavior is consistent with excited-state absorption (reverse saturable absorption) as a mechanism. We suggest that a higher threshold for optical limiting compared with that of C(60) in toluene is due to(More)
Femtosecond time-resolved reflectivity was measured near the 1.55 mm absorption edge of several GaAsxSb12x /AlSb quantum well samples. On the basis of differences in the reflectivity recovery kinetics and plateau values, we deduce that G – L intervalley scattering can be effectively suppressed for x>0.19. This is consistent with calculations incorporating(More)
Poor thermal stability has remained a severe obstacle for practical applications of optical fiber amplifiers based on quantum dots (QDs). We demonstrate that thermal stability at elevated temperatures can be achieved by using oleic-acid-capped QDs. Optical fiber amplifiers using oleic-acid-capped QDs for the gain medium exhibited stable gain of more than 5(More)