Sökning: "GaAs AlGaAs"

Visar resultat 16 - 20 av 41 avhandlingar innehållade orden GaAs AlGaAs.

  1. 16. Development of 1.3-μm GaAs-based vertical-cavity surface-emitting lasers

    Författare :Petrus Sundgren; Mattias Hammar; Harri Lipsanen; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik; Physics; Fysik;

    Sammanfattning : Long-wavelength vertical-cavity surface-emitting lasers (VCSELs) are desirable as low-cost sources for optical metropolitan-area and access networks. In the development of 1.3-µm VCSELs, most attention today is given to monolithic GaAs-based solutions, although no established active material exists in this wavelength region. LÄS MER

  3. 17. Electron Transport in Low Dimensional Systems

    Författare :Peter Ramvall; Fasta tillståndets fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; high mobility; low-dimensional structures; III-V semiconductors; quantum wells; heterojunctions; quantum Hall effect; edge channels; Shubnikov-de Haas effect; alloy-disorder scattering; Y-branch switch; two dimensional electron gas; Fysik; Fysicumarkivet A:1996:Ramvall; Physics; spin splitting; mag;

    Sammanfattning : This thesis consists of experimental studies of transport properties in high mobility two dimensional electron gases (2DEGs). Two material systems are used, an AlGaAs/GaAs heterojunction and a GaInAs/InP quantum well. LÄS MER

  4. 18. Studies of Novel Nanostructures by Cross- sectional Scanning Tunneling Microscopy

    Författare :Lassana Ouattara; Synkrotronljusfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Dilute ferromagnetic semiconductors Superlattices; Cross-sectional scanning tunneling microscopy; Semiconductor nanostructures; Fysik; Physics; Epitaxy; Quantum dots; Nanowires;

    Sammanfattning : This thesis presents structural and morphological studies of semiconductor nanostructures, namely quantum dots, nanowires and a dilute ferromagnetic semiconductor. These nanostructures are investigated on the atomic scale using cross-sectional scanning tunneling microscopy (XSTM). LÄS MER

  5. 19. Long-Wavelength Vertical-Cavity Lasers : Materials and Device Analysis

    Författare :Sebastian Mogg; KTH; []
    Nyckelord :VCL; VCSEL; vertical-cavity laser; semiconductor laser; long-wavelength; DBR; characterization; analysis; InP; InGaAs; quantum well; numerical modeling;

    Sammanfattning : Vertical-cavity lasers (VCLs) are of great interest as lightsources for fiber-optic communication systems. Such deviceshave a number of advantages over traditional in-plane laserdiodes, including low power consumption, efficient fibercoupling, on-chip testability, as well as potential low-costfabrication and packaging. LÄS MER

  7. 20. Leveraging HVPE for III-V/Si Integration and Mid-Infrared Photonic Device Fabrication

    Författare :Axel Strömberg; Yan-Ting Sun; Sebastian Lourdudoss; Mattias Hammar; Charles Cornet; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; HVPE; III-V Si; Photovoltaics; PEC; MIR; non-linear optics; QPM; QCL; Energiteknik; Energy Technology;

    Sammanfattning : This work covers the implementation of highly specialized epitaxial techniques enabled by the near-equilibrium hydride vapor-phase epitaxy growth process in III-V/Si integration for Si-based tandem solar cells and photoelectrochemical reactions, quasi phase matching GaP structures on GaAs substrates, and regrowth of InP:Fe on quantum cascade lasing structures.III-V/Si integration is an important topic in several fields of research with a significant one being solar energy harvesting. LÄS MER