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Anti-Stokes generation in a continuous wave raman laser: Author: Murphy, Sytil Kathleen; Date: 2008-08-15; Program: Physics; Abstract: The continuous-wave raman laser system differs from other raman systems in that it uses cavity enhancement to augment the pump laser source rather than a high-power pulsed laser source. Through interactions of the pump laser with the raman active medium, all raman systems can produce both red-shifted, Stokes, emission and blue-shifted, anti-Stokes, emission. Previous, continuous-wave raman laser systems have focused on the Stokes emission. This dissertation presents theory and data on the anti-Stokes emission. Specifically, it investigates the anti-Stokes mode structure and the emitted power a...; Download File | View full details

Building a raman laser pump source capable of generating flexible pulse durations while maintaining high spatial quality: Author: Wagemann, Stephen Scott; Date: 2009-05-15; Program: Physics; Abstract: A detailed characterization of a raman pump laser throughout the construction process is reported. Due to specific requirements for the pulsed raman experiment, there were no commercially available pump lasers capable of meeting our specifications. The pump source must produce high energy pulses of 50mJ to 100mJ with variable duration centered at 200ns. To create this pump source, the pulses are gated from a CW source and then amplified with a high gain Nd:YAG amplification system. High spatial quality is also a necessity as the laser needs to be coupled into a small diameter waveguide functio...; Download File | View full details

Soil Penetrometer with Ramon Sampling, Fluorescence and Reflected Light Imaging: A Feasibility Study: Author: Kadiri, Youssef; Date: 2005-05-15; Program: Electrical Engineering; Abstract: This thesis describes the feasibility and capabilities of a Fluorescence Imaging and raman Probe (FIRP). This miniature instrument will combine reflected light and fluorescence imaging and raman spectroscopy for potential exobiology or terrestrial environmental use. With the help of a penetrometer, the probe might be used to assess the presence of life on Mars and gain an understanding of Martian soil. Furthermore, this thesis will delineate how this penetrometer may be used to detect underground constituents and pollutants present on our own planet. The proposed FIRP will be incorporated into...; Download File | View full details

Mode-Locked Ramam Laser in H2 Pumped by a Mode-Locked External Cavity Diode Laser: Author: Xiong, Yihan; Date: 2007-08-15; Program: Physics; Abstract: In this thesis, a theory is first presented for a far-off resonance mode-locked raman laser in H2 with high finesse cavity enhancement. The theoretical derivation for the mode-locked raman laser is based on semiclasscial laser theory and time-dependent continuous wave (CW) raman theory. Numerically calculated results, including the intracavity fields' amplitude and phase evolution and output Stokes power versus input pump power are discussed in three different regimes depending on the relationship between the coherence dephasing rate and the repetition rate of the mode-locked pump laser. Then...; Download File | View full details

A combined confocal imaging and raman spectroscopy microscope for in vivo skin cancer diagnosis: Author: Arrasmith, Christopher Lyman; Date: 2008-12-15; Program: Electrical Engineering; Abstract: Confocal microscopy has provided a useful tool for imaging biopsied tissue samples. The cross sectioning ability inherent in confocal microscopes provides a method for viewing of cellular structure at different layers of a histology sample, allowing for optical cross sectioning and viewing structures below the surface of the sample. As a cancer diagnosis technique, confocal microscopy has been shown to provide valuable information showing differences in cell morphology of malignant and benign regions. raman spectroscopy has also been shown to be a useful tool for cancer diagnosis in skin tissu...; Download File | View full details

Reduction of EDFA optical power transients using power shaping: Author: Jackson, James Trent; Date: 2008-08-15; Program: Electrical Engineering; Abstract: Many erbium doped fiber amplifier (EDFA) based multi-wavelength optical networks employ techniques such as burst-switching or packet switching where the time interval between traffic blocks can be long enough to induce EDFA optical power transients. The optical power transients are created by abrupt changes in the average input power to the EDFAs and can adversely affect the performance of the network. To mitigate the effects of EDFA optical power transients on optical networks, a method called power shaping where heads and tails are joined to the beginning and end of a traffic block is invest...; Download File | View full details

Water Vapor Profiling using a Widely Tunable Amplified Diode Laser Differential Absorption Lidar (DIAL): Author: Obland, Michael Drew; Date: 2007-05-15; Program: Physics; Abstract: Water vapor is one of he most significant constituents of the atmosphere because of its role in cloud formation, precipitation, and interactions with electromagnetic radiation, especially its absorption of longwave infrared radiation. Some details of the role of water and related feedback mechanisms in the Earth system need to be characterized better if local weather, global climate, and the water cycle are to be understood. Water vapor profiles are currently obtained with several remote sensing techniques, such as microwave radiometers, passive instruments like the Atmospheric Emitted Radianc...; Download File | View full details