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Thesis (M.S.)--Rochester Institute of Technology, 1992. / Typescript. Includes bibliographical references.

Thesis (M.A.)--University of North Texas, May, 2009. / Title from title page display. Includes bibliographical references.

Dissertation (Ph.D.)--Worcester Polytechnic Institute. / Keywords: laser beam characteristics; heat transfer; hole profile; MEMS; hole formation; laser micromachining; laser microdrilling; plasma effects; silicon; 304 stainless steel; Fourier theory; lattice-phonon vibration. Includes bibliographical references. (p.379-390)

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 137-141). Also available in electronic version.

The Stark field perturbed spectra of near infrared vibrational overtones of hydrogen fluoride and acetylene have been measured with a high resolution molecular beam laser spectrometer. A high performance laser power build-up cavity (optical resonator) was constructed to measured the weak ro-vibrational transitions of the v₂ + 3v₃ vibrational combination band of acetylene. The measured gain of the build-up cavity was found to be at least 300 out of a potential 2000. The primary reason for the lower than expected gain was attributed to losses induced by the extreme heat build-up on the mirror surfaces. The electric dipole moment for the v = 3 vibrational overtone of hydrogen fluoride was determined to be 1.9614 ± 0.0021 Debye. This result was compared with predictions from the available theoretical models and some theoretical constants were revised based on the current contribution to dipole moment function of hydrogen fluoride. The Stark field perturbed spectra of the v₁ + 3v₃ and v₂ + 3v₃ vibrational combination bands of acetylene were analysed for their polarisability tensors. In order to complete the study, the ground electronic state static polarisability and anisotropy of the polarisability were also determined. They were found to be 3.96A³ and 1.071 ± 0.014A³, respectively. The |1030⁰0⁰> state (v₁ + 3v₃) was observed to be coupled with the |0040⁰0⁰> infrared forbidden state (4v₃) in the presence of the Stark electric field. The resultant analysis produced values of 4.62 ± 0.09A³ for the polarisability and 1.15 ± 0.03A³ for the polarisability anisotropy of the |1030⁰0⁰> state. The difference in energy between |1030⁰0⁰> and |0040⁰0⁰> was determined to be 4.133 cm⁻¹, which compares well with local mode calculations. The measurements of the v₂ + 3v₃ band indicated that the |0130⁰0⁰> state was strongly coupled with another infrared allowed, unidentified (rogue), state in the absence of the Stark field as well as with the infrared forbidden, |1120⁰0⁰> state in the presence of the Stark field. The previously unobserved J = 5 ← 4 transition of the infrared allowed rogue state was recorded here for the first time. The Stark field perturbed spectra of the R(3) and R(5) ro-vibrational transitions of the v₂ + 3v₃ band also showed evidence of rogue transitions. The ensuing analysis determined that the |0130°0°) state has a polarisability of 3.5 ± 0.3A³ and a polarisability anisotropy of 5.6 ± 1.8A³. The Stark field perturbed spectra of the R(3) and R(5) transitions were fit to a non-crossing model and the energy levels of the rogue J = 4 and J = 6 states were determined. The energy level difference between |0130°0°) and |1120°0°) was determined to be -11.88±0.22 cm⁻¹. This does not compare well with local mode calculations and it is possible that the perturbations due to the presence of the rogue state impeded the accurate determination of the energy level difference. The identity of the rogue vibrational state could not be determined from the data presented in this thesis alone. However, collaborative work with another research group suggests that the rogue vibrational state is |0306°3¹) (see Chapter 7). / Graduate

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The effect of atmospheric turbulence on an optical wave can seriously degrade the reliability of an optical communication link. One atmospheric effect is scintillation, which is caused by index of refraction fluctuations. Several observations of atmospheric turbulence statistics suggest a modest change in the power law behavior of Kolmogorov' s power spectral density model. The corresponding index of refraction fluctuations are assumed to have spatial power spectra that obey power laws that deviate somewhat from the classical - 11/3 power law. The purpose of this study is to develop analytical models for scintillation and other wave propagation statistics based on non-classical power spectra. This involves random processes, asymptotic theory, and evaluating integrals involving special functions (Bessel functions and hypergeometric functions). Mean irradiance and scintillation index models are derived for a Gaussian-beam wave propagating through an atmosphere experiencing weak irradiance fluctuations. Also, the wave structure function for an unbounded plane wave and spherical wave is derived under weak turbulence theory. Using the derived plane wave structure function, the scintillation index for both a plane and spherical wave experiencing strong irradiance fluctuations is calculated. In addition, a scintillation model that is valid under all irradiance fluctuation conditions is derived for both a plane and spherical wave propagating through non-Kolmogorov atmospheric turbulence.