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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Optical and electrical characteristics of Cr and Fe doped ZnSe thin film and bulk materials for optically and electrically pumped lasers

Gallian, Andrew. January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Alabama at Birmingham, 2006. / Additional advisors: Renato Camata, Richard Fork, Andrei Stanishevsky, Charles L. Watkins, Mary Ellen Zvanut. Dissertation not released until Fall 2007. Description based on contents viewed Oct. 6, 2007; title from title screen. Includes bibliographical references (p. 94-102).
2

Tunable devices for wavelength-division multiplexing communications. / CUHK electronic theses & dissertations collection

January 2000 (has links)
by Mak Wing-keung. / "August 2000." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
3

The construction and computational modeling of a fiber Bragg grating tunable laser diode

Winz, Michele W. 27 August 2003 (has links)
The widespread adoption of wavelength division multiplexing to increase the bandwidth of optical fiber communication systems has provided a major impetus for research on low cost, single-mode, wavelength stable tunable diode lasers for use in optical telecommunications due to the large volume of lasers required. Other applications, such as demodulation of fiber Bragg grating sensor systems can also make use of inexpensive tunable laser diodes. In addition, the steady increase in the amount of computational power available has led to the widespread use of computers to model physical systems both to predict system performance and to gain insight into physical behavior. Following a brief review of the application and construction of optical fiber Bragg gratings and a discussion of diode lasers and common methods of tuning diode laser wavelengths, a coupled-cavity approach to modeling laser diode output spectra, the construction of a fiber Bragg grating wavelength tunable laser, and the coupled cavity model of the fiber Bragg grating wavelength tunable diode laser are detailed. The physical laser system consists of a commercial Fabry-Perot diode laser with a cavity length of 300 microns, antireflection coated with a single layer of SiO, and coupled into an optical fiber containing a fiber Bragg grating. Wavelength tuning is accomplished by applying axial strain to the fiber grating. The coupled cavity model directly includes the antireflection coating, includes the fiber Bragg grating as an index step, and is the first reported implementation of this method to model fiber Bragg grating coupled laser diodes. The measured output spectra of the physical laser diode system and the calculated output spectra are given and compared. Continuous tuning of the diode laser by applying axial strain to the fiber grating is not observed nor calculated to occur for a single-layer silicon monoxide antireflection coating. To achieve continuous wavelength tuning, better antireflection coatings will need to be developed. / Graduation date: 2004
4

Swept-frequency sampled grating distributed Bragg reflector lasers optimized for optical coherence tomography applications a thesis /

George, Brandon J. Derickson, Dennis. January 1900 (has links)
Thesis (M.S.)--California Polytechnic State University, 2009. / Mode of access: Internet. Title from PDF title page; viewed on Jan. 20, 2010. Major professor: Dr. Dennis Derickson. "Presented to the Electrical Engineering Department faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Electrical Engineering." "December, 2009." Includes bibliographical references (p. 111).
5

Stable continuous-wave operation of Ti:Sapphire lasers in higher-order transverse Hermite-Gaussian modes

Poutous, Menalaos 12 1900 (has links)
No description available.
6

Synchronization of coupled solid-state lasers

Thornburg, Kennerly Scott, Jr. 05 1900 (has links)
No description available.
7

High repetition rate tunable lasers

Evans, Ian Jason January 1993 (has links)
Copper vapour laser (CVL) pumped dye lasers offer a source of high power, kilohertz repetition rate, tunable narrow-bandwidth radiation suitable for many spectroscopic applications in the visible and infra-red. Furthermore, the nonlinear frequency conversion of CVL-pumped dye laser radiation extends the wavelength range of these laser sources into the blue and ultra-violet. A series of experimental investigations have been undertaken to gain a physical understanding of the fundamental parameters necessary for the optimization of the CVL-pumping of dye lasers. Issues addressed include the influence of the CVL cavity design, the pump beam polarization and geometry, the dye oscillator cavity design, the choice of grating materials, and the dye flow rate. A model based on the rate equation analysis of the kinetic processes relevant to optical amplification in dye lasers has been developed, and the results have been used to design amplifiers with extraction efficiencies in excess of 45 %. As a result of the aforementioned investigations, three commercially available pulsed dye lasers have been successfully optimized for CVL-pumping for the first time. Once modified, these dye lasers have typically shown conversion efficiencies in excess of 20%, with frequency bandwidths as narrow as 800MHz, and beam qualities approaching the diffraction limit. The theory of second harmonic generation is reviewed, and a suite of corresponding computer models have been developed to form the basis for a coherent experimental investigation of UV generation using the CVL and CVL-pumped dye lasers. CVL SHG has been demonstrated in jS-barium borate (BBO) and lithium triborate (LBO), with SHG efficiencies in excess of 18% realized for the CVL 511nm line in BBO. For the first time, an experimental comparison of spherically and elliptically focused second harmonic generation has been undertaken. Optimized elliptical focusing is found to be up to 30% more efficient than using conventional spherical focusing in agreement with theoretical predictions. The superior divergence and transverse coherence of CVL-pumped dye lasers, in comparison to those of the CVL, is reflected in the SHG efficiencies achieved in BBO, LBO and lithium iodate. Conversion efficiencies approaching 40% have been demonstrated in lithium iodate, with harmonic conversion coefficients approaching 2400mW/W2 realized at low input powers. The Boyd and Kleinman theory of SHG with focused Gaussian beams is found to provide an excellent description of SHG with CVL-pumped dye laser radiation, and accurately predicts the optimum strength of focusing and harmonic conversion coefficient. For the first time, sum frequency mixing (SFM) of the CVL with a dye laser has been demonstrated, and found to provide a potentially efficient source for tunable UV radiation. Finally, the application of CVL-pumped dye lasers to resonant ionization mass spectrometry and tropospheric hydroxyl (OH) radical detection is discussed, and the spectroscopic potential of a frequency doubled CVL-pumped dye is demonstrated by recording the absorption spectrum of OH at 308nm.
8

High speed wavelength tuning of SGDBR lasers for optical coherence tomography applications : a thesis /

Maher, Benjamin James. Derickson, Dennis. January 1900 (has links)
Thesis (M.S.)--California Polytechnic State University, 2008. / Mode of access: Internet. Title from PDF title page, viewed on March 26, 2009. Major professor: Dennis Derickson, Ph.D. "Presented to the Electrical Engineering Department Faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the Master of Science degree in Electrical Engineering." "December 2008." Includes bibliographical references (p. 93-94). Will also be available on microfiche.
9

Tunable femtosecond lasers with low pump thresholds

Oppo, Karen January 1996 (has links)
The work in this thesis is concerned with the development of tunable, femtosecond laser systems, exhibiting low pump threshold powers. The main motive for this work was the development of a low threshold, self-modelocked Ti:Al2O3 laser in order to replace the conventional large-frame argon-ion pump laser with a more compact and efficient all-solid-state alternative. Results are also presented for an all-solid-state, self-modelocked Cr:LiSAF laser, however most of this work is concerned with self-modelocked Ti:Al2O3 laser systems. In chapter 2, the operation of a regeneratively-initiated, and a hard-aperture self- modelocked Ti:Al2O3 laser, pumped by an argon-ion laser, is discussed. Continuous- wave oscillation thresholds as low as 160mW have been demonstrated, along with self-modelocked threshold powers as low as 500mW. The measurement and suppression of phase noise on modelocked lasers is discussed in chapter 3. This is followed by a comparison of the phase noise characteristics of the regeneratively-initiated, and hard-aperture self-modelocked Ti:Al2O3 lasers. The use of a synchronously-operating, high resolution electron-optical streak camera in the evaluation of timing jitter is also presented. In chapter 4, the construction and self-modelocked operation of an all-solid-state Ti:Al2O3 laser is described. The all-solid-state alternative to the conventional argon-ion pump laser was a continuous-wave, intracavity-frequency doubled, diode-laser pumped Nd:YLF ring laser. At a total diode-laser pump power of 10W, this minilaser was capable of producing a single frequency output of ~1W, at 523.5nm in a TEM00 beam. The remainder of this thesis looks at the operation of a self-modelocked Ti:Al2O3 laser generating ultrashort pulses at wavelengths as long as 1053nm. The motive for this work was the development of an all-solid-state, self- modelocked Ti:Al2O3 laser operating at 1053nm, for use as a master oscillator in a Nd:glass power chain.
10

Laser source, image processing and fast imaging technology for opticalcoherence tomography

Cheng, Ho-yiu., 鄭浩堯. January 2010 (has links)
published_or_final_version / Electrical and Electronic Engineering / Master / Master of Philosophy

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