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This phenomenological multiple case study explored five first-year special education teachers' transfer of knowledge and skills learned in their preparation program to their professional setting and the support provided through their school system induction programming. I employed Baldwin and Ford's (1988) Model of Training Transfer and Rolfe et al.'s (2001) Critical Reflection as a framework to learn about their experiences and reflections on the transfer of learning from pre-service to in-service training and instruction. Data were collected through semi-structured interviews, survey responses, and artifact analysis. Participant skills and knowledge of instructional High-Leverage Practices (HLPs) included themes related to the impact of pre-service teacher preparation program content, design, field-based experiences, and feelings of self-efficacy in the transition to their first year of teaching. As in-service teachers, participants noted the impact of the work environment, such as the demands of the role of a special educator, school system and teacher preparation program differences, and collaboration on implementation. Induction support themes related to New Educator Orientation content, use of time, and professional autonomy were identified. Additional findings on in-service professional learning experiences provided insight into the specific HLPs addressed through school system training and mentor or administrator support. Transfer and reflection themes related to observation of their instruction, the importance of feedback for growth, and ongoing professional learning opportunities emerged. These study results may inform teacher preparation and school system induction year programming for beginning special education teachers. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

Most academic literature examining the political history of al-Jamahiriyah not only reduces power into a mere question of failing structures and the supremacy of Mu’ammar Qadhdhafi, but also triggers the disappearance of Libyans from their own history. In response, this study relies on a conceptual framework that looks at power and resistance as socio-cultural and dialogical processes to be studied through the everyday life of people. It adopts a methodological approach that privileges the subjective experiences of Libyans and bases its empirical study on oral histories/narratives. At the intersection of political sociology and political anthropology, the work of Sara Ahmed, Laurent Berlant, Michel de Certeau, Michel Foucault, Achille Mbembe, James C. Scott and Slavoj Žižek is brought into critical dialogue to investigate and cloud the distinction between power and resistance in the everyday. The interrelated findings of the study, divided across four chapters, reveal, firstly, how power is experienced as imposed, focusing on the disciplinary effects of violence, surveillance and fear over people’s everyday lives. Secondly, they show that, while people constantly try to manipulate those controlling mechanisms, their attempts often end up sustaining the power of the regime. This aspect emerges in people’s interactions with the ideological symbols and structures of the regime. In such a situation, humor, dissimulation and corruption play a very ambiguous role in mocking and maneuvering power, while (re)producing its mechanisms. Thirdly, the study outlines how quotidian fantasies and desires shape dynamics of power and resistance, showing the gradual emergence of popular hopes for a more consumerist and modern Libya. The complex array of dynamics that characterised the political anatomy of the everyday during al-Jamahiriyah becomes relevant for the revolutionary events of 2011, which led to its fall. The fourth thematic chapter shows the necessity to comprehend the everyday role of people in sustaining those dynamics of power and resistance in the present, following the fall of al-Jamahiriyah. The study sheds light on the empirical complexity of power and resistance and those spaces in-between, and thereby contributes not only to the theoretical understanding of mundane aspects of power and political authority, but also to the study of Libya and, more generally, the Middle East.

The Semiconductor Industry Association's (SIA) current National Technological Roadmap calls for the development of a suitable dielectric material for use in gate oxide for the 0.18|micrometers generation of chips and beyond. Some of the key challenges identified are resistance to oxide trapped charge generation from higher levels of tunneling currents and/or plasma processing, and formation of an effective barrier to dopant penetration during the gate processing. One promising material to meet these challenges is nitrided thermal oxide. Development of a growth process that yields high quality, lOnm thick, thermally grown Si02 films at RJT for use as a gate dielectric is described. Thin oxides (8nm - 20nm) were grown by thermal oxidation followed by inert anneals in Ar and N2. Nitrided oxides were created by implanting N2 (dose range: 5el3 - lei 5 /cm2) into the substrate prior to gate oxidation. Test equipment was setup to study Fowler Nordheim (FN) tunneling and dielectric breakdown. Test structures consisted of conventional and novel MOS capacitor structures with aluminum and poly-silicon gate electrodes. Scaling RJT's existing, 20nm oxidation process to lOnm resulted in degradation of dielectric strength from > lOMV/cm to ~6-7MV/cm for Al-gate MOS capacitors. Replacing the Al gate material with poly-silicon restored the dielectric strength to lOMV/cm. Performing an N2 implant through a screening oxide, prior to gate oxidation, was investigated as a means of obtaining a nitrided thermal oxide. For certain doses (5el3 - 5el4 /cm2), Al-gate MOS capacitors exhibited an improved dielectric strength as the mean value increased from 6- 7MV/cm to ~9MV/cm. Poly-Si gate MOS capacitors showed a similar improvement for the nitrided oxides, exhibiting mean dielectric strength values in the 10-12MV/cm range. Fowler- Nordheim (FN) tunnel current measurements showed that the nitrided films exhibit lower leakage levels and less charge trapping than their thermal Si02 counterparts. Results indicate that a 12nm nitrided oxide, for a certain dose (5el4/cm2), exhibited equivalent electrical performance to a 20nm thermally grown Si02 oxide. In conclusion, a process was developed for yielding reliable thin gate oxides (~10nm) in a university fab.

The vast majority of optical components and devices in use today can be grouped under the umbrella of ``bulk optics''; i.e. they generally have a non-negligible thickness compared to the wavelength of light. This is true of components from lenses to wave plates to Fabry-Perot etalons, all of which need sufficient thickness such that light waves can accumulate an appropriate amount of phase upon propagation through the structure. In this thesis, we develop and explore a variety of optical components that are thin compared to the wavelength of light and lie at the interface between two materials (i.e. a substrate and air). We explore approaches to filter, absorb, redirect, and re-shape light with flat, ultra-thin structures which are easy to fabricate with modern micro- and nanofabrication techniques., Engineering and Applied Sciences

Since their initial demonstration in 1994, quantum cascade lasers (QCLs) have become prominent sources of mid-infrared radiation. Over the years, a large scientific and engineering effort has led to a dramatic improvement in their efficiency and power output, with continuous wave operation at room temperature and Watt-level output power now standard. However, beyond this progress, new functionalities and capabilities need to be added to this compact source to enable its integration into consumer-ready systems. Two main areas of development are particularly relevant from an application standpoint and were pursued during the course of this thesis: wavelength control and wavefront engineering of QCLs. The first research direction, wavelength control, is mainly driven by spectroscopic applications of QCLs, such as trace gas sensing, process monitoring or explosive detection. We demonstrated three different capabilities, corresponding to different potential spectroscopic measurement techniques: widely tunable single longitudinal mode lasing, simultaneous lasing on multiple well-defined longitudinal modes, and simultaneous lasing over a broad and continuous range of the spectrum. The second research direction, wavefront engineering of QCLs, i.e. the improvement of their beam quality, is relevant for applications necessitating transmission of the QCL output over a large distance, for example for remote sensing or military countermeasures. To address this issue, we developed plasmonic lenses directly integrated on the facets of QCLs. The plasmonic structures designed are analogous to antenna arrays imparting directionality to the QCLs, as well as providing means for polarization control. Finally, a research interest in plasmonics led us to design passive flat optical elements using plasmonic antennas. All these projects are tied together by the involvement of Fourier analysis as an essential design tool to predict the interaction of light with various gratings and periodic arrays of grooves and scatterers., Engineering and Applied Sciences

The coupling of macroscopic objects via the optical near-field can generate strong attractive and repulsive forces. Here, I explore the static and dynamic optomechanical interactions that take place in a geometry consisting of a silicon nanomembrane patterned with a square-lattice photonic crystal suspended above a silicon-on-insulator substrate. This geometry supports a hybridized optical mode formed by the coupling of eigenmodes of the membrane and the silicon substrate layer. This system is capable of generating nanometer-scale deflections at low optical powers for membrane-substrate gaps of less than 200 nm due to the presence of an optical cavity created by the photonic crystal that enhances both the optical force and a force that arises from photo-thermal-mechanical properties of the system. Feedback between Brownian motion of the membrane and the optical and photo-thermal forces lead to dynamic interactions that perturb the mechanical frequency and linewidth in a process known as ``back-action.'' The static and dynamic properties of this system are responsible for optical bistability, mechanical cooling and regenerative oscillations under different initial conditions. Furthermore, solid objects separated by a small distance experience the Casimir force, which results from quantum fluctuations of the electromagnetic field (i.e. virtual photons).The Casimir force supplies a strong nonlinear perturbation to membrane motion when the membrane-substrate separation is less than 150 nm. Taken together, the unique properties of this system makes it an intriguing candidate for transduction, accelerometry, and sensing applications., Engineering and Applied Sciences

The emergence of nanostructured semiconducting materials enables new approaches toward the realization of photodetectors that operate in the technologically important near- and short-wave infrared (NIR and SWIR) spectral ranges. In particular, organic semiconductors and colloidal quantum dots (QDs) possess numerous advantages over conventional crystalline semiconductors including highly tunable optical and electronic characteristics, the prospect for low-temperature processing, and compatibility with inexpensive and exible substrates. Photodetectors based on such materials may lead to low-cost IR focal plane arrays for night-vision imaging as well as a multitude of novel applications in biological and chemical sensing. This thesis describes the development and detailed characterization of several photodetectors that incorporate colloidal QD and organic semiconductor thin films as active layers. The electronic properties of PbS QDs are thoroughly investigated in a field effect transistor (FET) geometry and several QD-based photoconductive structures exhibiting SWIR photosensitivity are demonstrated. We describe a novel QD-sensitized lateral heterojunction photoconductor in which the functions of optical absorption and charge transport are dissociated into different physical layers that can be independently optimized. This structure is advantageous because it obviates the need for aggressive chemical treatments to the QD film that may compromise the quality of QD surface passivation. Photovoltaic device architectures are addressed, noting their advantages of being operable without an external applied bias and at fast response speeds. We present detailed experimental and theoretical characterization of a photovoltaic structure that is sensitized at NIR wavelengths by a J-aggregating cyanine dye. The high absorption coefficient of the J-aggregate film, combined with the use of a reflective anode and optical spacer layer, enables an external quantum efficiency (EQE) of \(16.1\pm0.1\%(\lambda = 756 nm)\) to be achieved at zero-bias in a device that incorporates an \(8.1\pm0.3 nm\)-thick dye film. The merits and drawbacks of the various device architectures and nanostructured material systems are discussed and the outlook for nanostructured photodetectors that exhibit infrared sensitivity is presented., Engineering and Applied Sciences