Sökning: "oxygen doping"

Visar resultat 11 - 15 av 61 avhandlingar innehållade orden oxygen doping.

1. 11. Doping of high-Al-content AlGaN grown by MOCVD

   Författare :Daniel Nilsson; Anelia Kakanakova- Georgieva; Erik Janzén; Michelle Moram; Linköpings universitet; []
   Nyckelord :;

   Sammanfattning : The high-Al-content AlxGa1-xN, x > 0.70, is the principal wide-band-gap alloy system to enable the development of light-emitting diodes operating at the short wavelengths in the deep-ultraviolet, λ < 280 nm. LÄS MER

3. 12. Structure and properties of FeAl as influenced by processing

   Författare :HELENA SKOGLUND; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; EDS; mechanical alloying; FeAl; Al2O3 precipitates; boron-doping; powder processing; diffusion; vacancies; mechanical properties; hardening mechanisms;

   Sammanfattning : Iron aluminides are candidate materials for a sustainable society since they are composed of abundant metals and have excellent corrosion properties in combination with high specific strength. However, there are some drawbacks that limit the practical use, e.g. low RT ductility and a drop in strength at high temperature. LÄS MER

4. 13. Intrinsic tunneling spectroscopic investigations of Bi2Sr2CaCu2O8+x superconductors : The fluxon lattice, resonant phenomena,flux-flow and current doping

   Författare :Holger Motzkau; Vladimir M. Krasnov; Paul Müller; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : In this thesis, the tunneling between individual atomic layers in structures of Bi2Sr2CaCu2O8+x based high-temperature superconductors are experimentally studied employing the intrinsic Josephson effect. A special attention is paid on the fabrication of small mesa structures using micro and nanofabrication techniques. LÄS MER

5. 14. Proton conductivity of lanthanum and barium zirconate: Microscale aspects on first-principles basis

   Författare :Joakim Nyman; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; first principles; trapping; conductivity; grain boundary; segregation; pyrochlore; space charge; solid oxide fuel cell; depletion; electrolyte; La2Zr2O7; oxygen vacancy; BaZrO3; proton; DFT; point defect; perovskite; acceptor;

   Sammanfattning : Fuel cells are devices which convert chemical energy into electrical energy cleanly and efficiently. Development of fuel cells compatible with hydrocarbon fuels would make more efficient use of present fossil and renewable fuels, and also enable progress towards a future hydrogen economy. LÄS MER

7. 15. High-frequency phenomena in small Bi2Sr2CaCu2O8+x intrinsic Josephson junctions

   Författare :Holger Motzkau; Vladimir M. Krasnov; Reinhold Kleiner; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; high-temperature superconductivity; Bi-2212; cuprates; intrinsic Josephson junctions; intrinsic tunneling; fluxons; flux-flow oscillator; THz-emission; cavity resonances; polaritons; electrical doping; micro nano-fabrication; fysik; Physics;

   Sammanfattning : In this thesis, the tunneling between individual atomic layers in structures of Bi2Sr2CaCu2O8+x based high-temperature superconductors are experimentally studied employing the intrinsic Josephson effect. A special attention is paid to the fabrication of small mesa structures using micro and nanofabrication techniques. LÄS MER