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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 83 for “"semiconductor laser"”.
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Semiconductor Laser Device-Level Characteristics
<p>High-speed modulations of the semiconductor lasers are highly desirable in cost-effective optical communication systems. Developing the experimental setups to extract the characteristics of the semiconductor lasers is vital to the future of the optical research projects. In this thesis, …
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Development of Broadband Semiconductor Laser Frequency Combs
Quantum Cascade Laser (QCL) is a compact, mature and flexible coherent radiation source in both terahertz (THz) and mid-infrared (midIR) frequency range. Many molecules have rotational-vibrational absorption bands in midIR, making QCL-based dual comb spectroscopy (DCS) systems the ideal tool for …
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Advances in semiconductor laser mode and beam engineering
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2022-04-06 without embargo terms
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Semiconductor laser mode engineering via waveguide index structuring
Semiconductor laser diodes are used in many applications, and their performance is often strongly influenced by the optical mode properties. In this work, dielectric waveguides and their guided modes have been simulated and analyzed as relevant to semiconductor diode lasers. The transverse …
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Semiconductor Laser Arrays Grown by Metalorganic Chemical Vapor Deposition
… growth of ultrathin epitaxial layers of III-V semiconductor compounds. This vapor deposition process is well suited for the growth of high performance semiconductor laser structures. Experimental data have been collected on a variety of MOCVD grown laser structures and are presented along with …
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High-power semiconductor laser arrays by metalorganic chemical vapor deposition
Semiconductor injection lasers have the capability of producing very high output powers if a large array of diodes can be fabricated. The development of useful high power semiconductor lasers depends on fabrication processes which overcome the problems associated with high power laser operation. …
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Modeling of DFB surface emitting lasers and semiconductor laser arrays
Theoretical modeling of novel semiconductor laser systems, i.e., distributed-feedback (DFB) surface emitting lasers and semiconductor laser arrays, is presented. The DFB surface emitting lasers can produce stable single-mode outputs even under high bit-rate direct modulation and form …
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Semiconductor laser diode mode properties arising from engineered photonic crystals
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2025-08-01
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Investigation of Narrowband Acousto-Optic Tunable Filters for Semiconductor Laser Tuning
… tunable sources find applications in areas of laser surgery, optical coherence tomography, material processing, and differential absorption light detection and ranging. Acousto-optic tunable filters (AOTFs) are wavelength selective devices which allow for better stability than mechanical tuning …
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Design and characterization of semiconductor laser structures for hydrogen sensing applications
… time. Therefore, several platforms in which semiconductor lasers can be functionalized to detect hydrogen concentrations below the lower explosive limit have been developed. The laser structures were chosen such that there already exist well-established fabrication technologies, and the …
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Application of electroabsorption in a semiconductor laser for electromagnetic field sensing
… of electroabsorption in an AlGaAs quantum-well semiconductor laser device for optically based electromagnetic field sensing has been studied. A separate confinement heterostructure laser design containing a single quantum well and a steplike waveguiding index profile has demonstrated efficient …
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Fabrication and performance of broad-area high power narrow linewidth semiconductor laser diodes
… high-order, distributed feedback (DFB) grating, semiconductor laser diodes for the goal of manufacturably attaining longitudinal mode reduction. Through coupled-mode theory, the coupling coefficient, the reflectivity, and the laser emission linewidth resulting from a refractive index grating are …
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Ultralow-noise modelocked lasers
… and theory of ultralow-noise actively modelocked lasers are presented. We demonstrate quantum-limited noise performance of a hybridly modelocked semiconductor laser with an rms timing jitter of only 47 fs (10 Hz to 10 MHz) and 86 fs (10 Hz to 4.5 GHz). The daunting task of measuring ultralow-noise …
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Fabrication of quantum wire heterostructures and short wavelength photonic devices using the strain-induced lateral-layer ordering process
… underway on a variety of approaches to improve semiconductor laser performance. The use of quantum size effects has been studied for over 25 years. It has been predicted and shown that the incorporation of one-dimensionally confined quantum wells into laser devices can significantly improve …
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Bipolar thermoelectric devices
… considered, and particular attention is given to semiconductor laser diodes. The mechanisms that govern both internal heat exchange and heat transfer between a device and its environment are examined, leading to structures which are optimized for thermal management.
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Femtosecond pulse generation in surface-emitting semiconductor lasers
… pumped vertical external-cavity surface-emitting lasers (VECSELs). Continuous wave VECSELs were first designed as a type of semiconductor laser capable of producing high output power in near transform-limited beams. Optical pumping allows the output power of the device to be increased simply by …
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LOW-TEMPERATURE CHARACTERIZATION OF A 1.55-μm MULTIPLE-QUANTUM-WELL LASER DOWN TO 10 K
A ridge-waveguide 1.55-μm semiconductor laser with a multiple-quantum-well carrier confinement structure was characterized from room temperature down to 10 K. The temperature dependence of important laser parameters, such as threshold current, differential efficiency, emission wavelength, and …
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High-speed characterizations of single quantum-well transistor laser
The transistor laser (TL) is a unique three-terminal semiconductor laser device that possesses qualities and functionalities that cannot be achieved by diode lasers alone. In this thesis, the history of development and device structure, as well as the carrier dynamics in the TL will be first …
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Integrated Wavelength Stabilization Of Broad Area Semiconductor Lasers Using A Dual Grating Reflector
… scheme based on grating-coupled surface-emitting lasers is explored. This wavelength stabilization scheme relies on two gratings. The first grating is fabricated on the p-side of the semiconductor laser in close proximity to the laser waveguide such that it couples light out of the guided mode of …
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Dynamics and interactions of cavity solitons in photonic devices
… systems. Three systems are investigated - a semiconductor laser with optical injection, a semiconductor laser with frequency selective feedback and a nonlinear cavity with a Kerr material. Cavity solitons have common features which can be observed in all three systems as well as properties …
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