ABSTRACT
We present experimental results of photochromic reactions induced by single- and two-photon excitations in a poly(methyl methacrylate) thin film doped with spirobenzopyran. We also demonstrate the operation of a spirobenzopyran-doped poly(methyl methacrylate) planar waveguide, prepared by cast spinning the media onto fused-quartz slides. The following phenomena were shown to take place in this waveguide: single-twophoton coloring, f luorescing, and bleaching. The results indicate that such devices may be suitable for many applications, including optical waveguides, volume optical storage, and optical sensors.
ABSTRACT
We present an optical pulse delay (OPD) for delaying ultrashort optical pulses that uses an acousto-optic deflector as an active component. The OPD is designed to correct for chromatic dispersion caused by the significant color spectrum of ultrashort pulses. It is intended to be used as one of the components in a three-dimensional memory system based on pulse-collision addressing in two-photon materials. Calculations show that the OPD should be able to provide 65 arbitrary delays with a random access time of Ë 1 µs for 100-fs pulses. The power efficiency of the OPD can be as high as 85% and hence permits two units to be cascaded to provide more than 4000 distinct delays. The number of delays and the access time can be optimized such that a fewer number of delays are obtained with a shorter access time, which favors high-speed operations. We provide experimental results that use a Michelson interferometer to measure three different delays, approximately 1 mm apart (equivalent to Ë3-ps time delay), obtained with 130-fs pulses. In addition we include an analysis of the performance of acousto-optic devices for both monochromatic light and ultrashort pulsed lasers. Finally, we provide the design of the optical pulse-delay system for a three-dimensional memory application.
