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• 1. [Article] Pressure broadening and pressure shift of diatomic iodine at 675 nm

  xvi, 280 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.

  Citation × Citation Citation Abstract Copy Title: Pressure broadening and pressure shift of diatomic iodine at 675 nm Author: Wolf, Erich N. Year: 2010, 2009 xvi, 280 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Title: Pressure broadening and pressure shift of diatomic iodine at 675 nm Author: Wolf, Erich N. Year: 2010, 2009 xvi, 280 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Close

• 2. [Article] Fundamental Properties of Functional Zinc Oxide Nanowires Obtained by Electrochemical Method and Their Device Applications

  We report on the fundamental properties and device applications of semiconductor nanoparticles. ZnO nanowires and CdSe quantum dots were used, prepared, characterized, and assembled into novel light-emitting ...

  Citation × Citation Citation Abstract Copy Title: Fundamental Properties of Functional Zinc Oxide Nanowires Obtained by Electrochemical Method and Their Device Applications Author: Nadarajah, Athavan Year: 2012 We report on the fundamental properties and device applications of semiconductor nanoparticles. ZnO nanowires and CdSe quantum dots were used, prepared, characterized, and assembled into novel light-emitting diodes and solar cells. ZnO nanowire films were grown electrochemically using aqueous soluble chloride-based electrolytes as precursors at temperatures below 90° C. Dopants were added to the electrolyte in the form of chloride compounds, which are AlCl3, CoCl2, CuCl2, and MnCl2. The optical, magnetic, and structural properties of undoped and transition-metal-ion doped ZnO nanowires were explored. Our results indicate that the as-grown nanowire structures have considerable internal strain, resulting in clearly visible lattice distortions in bright and dark-field transmission electron micrographs. Photo and electroluminescence studies indicate that the strain-induced defects strongly dominate any dopant-related effects. However, annealing at moderate temperature as well as laser annealing induces strain relaxation and leads to dopant activation. Hence, the optical and electrical properties of the nanowires significantly improve, allowing these nanowires to become feasible for use in the fabrication of solar cell and LED devices. In addition, the magnetic impurities incorporated into our ZnO nanowires show superparamagnetic behavior at room-temperature, while Al-doped and undoped ZnO nanowires show no magnetic behavior. The electroluminescence (EL) is achieved from a vertical hybrid p-n junction LED arrangement consisting of a hole-conducting polymer and n-type ZnO nanowires, our group was the first to report this vertical nanowire-based LED in Könenkamp et al., 2004 [12]. The observed EL spectra show an ultraviolet excitonic emission peak and a broad defect-related emission band in the visible range. After annealing at 380° C, the defect related EL peak exhibits a characteristic shift to higher wavelengths, where the magnitude of the shift is dependent on the dopant type. Aluminum incorporation exhibited the most improved exciton related-emission, leading to the emergence of a narrow excitonic luminescence peak around 390 nm, which is close to the bandgap of ZnO. The comparison of spectra obtained from temperature-dependent photoluminescence (PL) measurements, before and after thermal annealing, also indicates that the optical activity of impurities changes noticeably upon annealing. The internal quantum efficiency for PL is measured to be as high as 16 percent for Al-doped samples annealed at 380° C. The PL measurements also show that the excitonic luminescence is preferentially guided, while the defect related emission is more isotropically emitted. The nanostructured heterojunction solar cell is designed such that thin CdSe quantum dot films are embedded between a ZnO nanowire film and a hole-conducting polymer layer. This arrangement allows for enhanced light absorption and an efficient collection of photogenerated carriers. Here, we present a detailed analysis of the pyridine solution and 1,2- ethanedithiol ligand exchange processes of the quantum dots, deposition processes of this quantum dot layer, the conformality of this layer on deeply nanostructured samples, and the effect of a surfactant-aided thermal annealing process. Annealing creates a structural conversion of the quantum dot layers into an extremely thin continuous poly-crystalline film, with typical grain diameters of 30-50 nm. This transition is accompanied by a loss of quantum confinement and a significant improvement of the charge transport in the CdSe layer. The combination of the solution and ligand exchange of CdSe quantum dots, as well as the deposition and optimized annealing processes of this quantum dot layer, resulted in solar cells with an open-circuit voltage up to 0.6 V, a short circuit current of ~15 mA/cm2, an external quantum efficiency of 70 percent, and an energy conversion efficiency of 3.4 percent. This 3.4 percent efficiency is presently one of the best efficiencies obtained for this type of device. Title: Fundamental Properties of Functional Zinc Oxide Nanowires Obtained by Electrochemical Method and Their Device Applications Author: Nadarajah, Athavan Year: 2012 We report on the fundamental properties and device applications of semiconductor nanoparticles. ZnO nanowires and CdSe quantum dots were used, prepared, characterized, and assembled into novel light-emitting diodes and solar cells. ZnO nanowire films were grown electrochemically using aqueous soluble chloride-based electrolytes as precursors at temperatures below 90° C. Dopants were added to the electrolyte in the form of chloride compounds, which are AlCl3, CoCl2, CuCl2, and MnCl2. The optical, magnetic, and structural properties of undoped and transition-metal-ion doped ZnO nanowires were explored. Our results indicate that the as-grown nanowire structures have considerable internal strain, resulting in clearly visible lattice distortions in bright and dark-field transmission electron micrographs. Photo and electroluminescence studies indicate that the strain-induced defects strongly dominate any dopant-related effects. However, annealing at moderate temperature as well as laser annealing induces strain relaxation and leads to dopant activation. Hence, the optical and electrical properties of the nanowires significantly improve, allowing these nanowires to become feasible for use in the fabrication of solar cell and LED devices. In addition, the magnetic impurities incorporated into our ZnO nanowires show superparamagnetic behavior at room-temperature, while Al-doped and undoped ZnO nanowires show no magnetic behavior. The electroluminescence (EL) is achieved from a vertical hybrid p-n junction LED arrangement consisting of a hole-conducting polymer and n-type ZnO nanowires, our group was the first to report this vertical nanowire-based LED in Könenkamp et al., 2004 [12]. The observed EL spectra show an ultraviolet excitonic emission peak and a broad defect-related emission band in the visible range. After annealing at 380° C, the defect related EL peak exhibits a characteristic shift to higher wavelengths, where the magnitude of the shift is dependent on the dopant type. Aluminum incorporation exhibited the most improved exciton related-emission, leading to the emergence of a narrow excitonic luminescence peak around 390 nm, which is close to the bandgap of ZnO. The comparison of spectra obtained from temperature-dependent photoluminescence (PL) measurements, before and after thermal annealing, also indicates that the optical activity of impurities changes noticeably upon annealing. The internal quantum efficiency for PL is measured to be as high as 16 percent for Al-doped samples annealed at 380° C. The PL measurements also show that the excitonic luminescence is preferentially guided, while the defect related emission is more isotropically emitted. The nanostructured heterojunction solar cell is designed such that thin CdSe quantum dot films are embedded between a ZnO nanowire film and a hole-conducting polymer layer. This arrangement allows for enhanced light absorption and an efficient collection of photogenerated carriers. Here, we present a detailed analysis of the pyridine solution and 1,2- ethanedithiol ligand exchange processes of the quantum dots, deposition processes of this quantum dot layer, the conformality of this layer on deeply nanostructured samples, and the effect of a surfactant-aided thermal annealing process. Annealing creates a structural conversion of the quantum dot layers into an extremely thin continuous poly-crystalline film, with typical grain diameters of 30-50 nm. This transition is accompanied by a loss of quantum confinement and a significant improvement of the charge transport in the CdSe layer. The combination of the solution and ligand exchange of CdSe quantum dots, as well as the deposition and optimized annealing processes of this quantum dot layer, resulted in solar cells with an open-circuit voltage up to 0.6 V, a short circuit current of ~15 mA/cm2, an external quantum efficiency of 70 percent, and an energy conversion efficiency of 3.4 percent. This 3.4 percent efficiency is presently one of the best efficiencies obtained for this type of device. Close

• 3. [Article] Cold atom control with an optical one-way barrier

  xvi, 176 p. : ill. (some col.)

  Citation × Citation Citation Abstract Copy Title: Cold atom control with an optical one-way barrier Author: Schoene, Elizabeth A., 1979- Year: 2011, 2010 xvi, 176 p. : ill. (some col.) Title: Cold atom control with an optical one-way barrier Author: Schoene, Elizabeth A., 1979- Year: 2011, 2010 xvi, 176 p. : ill. (some col.) Close

• 4. [Article] Radiation pressure cooling of a silica optomechanical resonator

  xi, 125 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.

  Citation × Citation Citation Abstract Copy Title: Radiation pressure cooling of a silica optomechanical resonator Author: Park, Young-Shin, 1972- Year: 2010, 2009 xi, 125 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Title: Radiation pressure cooling of a silica optomechanical resonator Author: Park, Young-Shin, 1972- Year: 2010, 2009 xi, 125 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Close

• 5. [Article] The effect of geometry and surface morphology on the optical properties of metal-dielectric systems

  xiii, 133 p. ; ill. (some col.) A print copy of this title is available through the UO Libraries. Search the library catalog for the location and call number.

  Citation × Citation Citation Abstract Copy Title: The effect of geometry and surface morphology on the optical properties of metal-dielectric systems Author: Hasegawa, Keisuke, 1977- Year: 2009, 2008 xiii, 133 p. ; ill. (some col.) A print copy of this title is available through the UO Libraries. Search the library catalog for the location and call number. Title: The effect of geometry and surface morphology on the optical properties of metal-dielectric systems Author: Hasegawa, Keisuke, 1977- Year: 2009, 2008 xiii, 133 p. ; ill. (some col.) A print copy of this title is available through the UO Libraries. Search the library catalog for the location and call number. Close

• 6. [Article] Metastability of copper indium gallium diselenide polycrystalline thin film solar cell devices

  xvi, 117 p. ; ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.

  Citation × Citation Citation Abstract Copy Title: Metastability of copper indium gallium diselenide polycrystalline thin film solar cell devices Author: Lee, Jinwoo, 1973- Year: 2009, 2008 xvi, 117 p. ; ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Title: Metastability of copper indium gallium diselenide polycrystalline thin film solar cell devices Author: Lee, Jinwoo, 1973- Year: 2009, 2008 xvi, 117 p. ; ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Close