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The subject of this dissertation is design, physics, and applications of organic photorefractive polymers which are a recently discovered new class of multifunctional polymeric composites suitable for real-time holographic recording. Design principles of amorphous guest-host photorefractive polymers are described, and their performance is investigated. Also, the use of these materials as recording media in dynamic holographic applications is evaluated. Diffraction efficiency of η ∼ 86%, limited only by absorption and reflection losses, two-beam coupling net gain coefficient of Γ = 200 cm⁻¹, and light-induced refractive index modulations as high as Δn =7x10⁻³ are demonstrated. Hologram growth rates of the order of 500 ms are observed with recording light intensities > 10 mW/cm² using either low-power laser diodes (675 nm) or a HeNe laser (633 nm). The materials have been synthesized that show good sensitivity in red and near-infrared part of the light spectrum. Physical mechanisms leading to high performance of photorefractive polymeric composites and the influence of the polymer composite structure on optical performance are investigated. The experimental results are compared with a phenomenological model based on Kukhtarev's equations. Experiments showing possible applications of PR polymers, such as dynamic time-average interferometry and document security verification are demonstrated.

A sodium laser guide star (LGS) adaptive optics (AO) system developed at Stewart Observatory is to be used at the 6.5m MMT. Annual measurements at Kitt Peak show that the mean mesospheric sodium column density varies from ∼2x10⁹cm⁻² (summer) to ∼5x10⁹cm⁻² (winter). The sodium column density also varies by a factor of two during a one hour period. The first simultaneous measurements of sodium LGS brightness, sodium column density and laser power were obtained. The absolute sodium return for a continuous wave circularly polarized beam is 1.2(±0.3)x10⁶ photons s⁻¹m⁻²W⁻¹ for the sodium column density of 3.7x10⁹cm⁻². Theoretical studies demonstrate that the 6.5m MMT LGS AO can provide Strehl ratios better than 0.15 and about 50% flux concentration within 0.2" aperture for 1-5.5μm under median seeing. This correction will be available for the full sky. Better Strehl and higher flux concentration can be achieved with natural guide stars, but limited sky coverage. The AO corrected field-of-view is about 60". The Arizona IR Imager and Echelle Spectrograph (ARIES) was designed to match the 6.5m MMT AO. Detection limits of more than 2 magnitude fainter can be reached with the AO over without the AO. A pre-ARIES wide field near-IR camera was designed, built and tested. The camera provides 1" images in the near-IR over an 8.5 x 8.5arcmin² field. The 10-σ detection limit with one minute exposures is 17.9 mag. in the K band. A prototype very high resolution cross-dispersed optical echelle spectrograph was designed and built to match the Starfire Optical Range 1.5m AO images. Interstellar KI 7698Å absorption lines have been detected in the spectra of αCyg and ζPer. The spectral resolution is 250.000. About 300Å wavelengths were covered in a single exposure. Total detection efficiency of 1% has been achieved. For the first time, a near-single-mode fiber with 10μm core size was applied to transmit the Mt. Wilson 100inch AO corrected beams to a spectrograph. The coupling efficiency of the fiber reached up to 70%. Spectra of αOri were recorded. The spectral resolution is 200,000. The total wavelength coverage is about 650Å per exposure.

<p> Optical gradient index media have the property where the spatial variation of the index of refraction is continuous along the direction transverse to the optical axis. Many emerging technologies in optics require gradient index components, and a firm understanding of the physics of light propagation in these components is required. Presented here are the mathematical foundations used to analyze light propagation in planar quadratic index profile waveguides. One transverse direction is used in this analysis, and light propagation is seen to have periodic behavior. Also presented here is a comparison of ray bundles and wave intensities in quadratic index waveguides, with the intent to use this machinery to further ray chaos theory.</p>

The room-temperature nonlinear absorption spectra of a GaInAs/AlInAs and a GaAlInAs/AlInAs multiple quantum well (MQW) were measured near 1.3 μm using a pump-probe technique. Saturation carrier densities at the heavy-hole exciton peak were determined to be 1.2 x 10¹⁸ and 1.0 x 10¹⁸ cm⁻³ with carrier lifetimes of ≃ 2.3 ns and ≃ 750 ps for the two samples, respectively. Fabry-Perot etalons with integrated mirrors grown by molecular beam epitaxy (MBE) with GaInAs/AlInAs MQWs as spacer layers were also fabricated as optical switching devices. A 175 ps recovery time was measured for the etalon at room temperature.

This thesis provides step by step instructions on how to design, layout, and fabricate diffractive optical elements (DOE). While there has been a great deal published on the design of DOEs, there are few publications detailing how to transform a design into a physical element. The thesis describes how to order a photomask and pattern an element. It provides recipes that I have used to etch DOEs with both an ion mill and a reactive ion etcher (RIE) at the Optical Sciences Center. The thesis includes characterization of the elements fabricated using these recipes. In addition the thesis looks at the design and fabrication of ring toric lenslets. A ring toric lenslet is a DOE that focuses light to a ring instead of a point. The ring toric lenslet has potential applications in the optical data storage industry. This thesis includes macros for the design and mask layout of binary and grayscale ring toric lenslets. Grayscale elements require special design, calibration, and mask layout steps not necessary for binary elements. Details of the design, calibration, mask layout, and fabrication of the grayscale element are included.