Sökning: "NATURVETENSKAP Fysik Kondenserade materiens fysik Halvledarfysik"

Visar resultat 16 - 20 av 44 avhandlingar innehållade orden NATURVETENSKAP Fysik Kondenserade materiens fysik Halvledarfysik.

1. 16. Design and fabrication of long wavelength vertical cavity lasers on GaAs substrates

   Författare :Rickard Marcks von Würtemberg; Mattias Hammar; Markus Amann; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; VCSEL; Selective Area Epitaxy; Epitaxial regrowth; Laser; Semiconductor physics; Halvledarfysik;

   Sammanfattning : Vertical cavity surface emitting lasers (VCSELs) are today a commodity on the short wavelength laser market due to the ease with which they are manufactured. Much effort has in the last decade been directed towards making long wavelength VCSELs as successful in the marketplace. LÄS MER

3. 17. Initial stages of metal- and organic-semiconductor interface formation

   Författare :Pål Palmgren; Mats Göthelid; Mikael Grehk; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Semiconductor physics; Halvledarfysik;

   Sammanfattning : This licentiate thesis deals with the electronic and geometrical properties of metal-semiconductor and organic-semiconductor interfaces investigated by photoelectron spectroscopy and scanning tunneling microscopy. First in line is the Co-InAs interface (metal-semiconductor) where it is found that Co is reactive and upon adsorption and thermal treatment it alloys with the indium of the substrate to form metallic islands, about 20 nm in diameter. LÄS MER

4. 18. Epitaxial growth optimization for 1.3-um InGaAs/GaAs Vertical-Cavity Surface-Emitting lasers

   Författare :Zhenzhong Zhang; Mattias Hammar; Nicolae Chitica; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; VCSEL MOVPE InGaAs GaAs quantum wells; Semiconductor physics; Halvledarfysik;

   Sammanfattning : Long-wavelength (1.3-μm) vertical-cavity surface-emitting lasers (VCSELs) are of great interest as low-cost, high performance light sources for fiber-optic metro and access networks. During recent years the main development effort in this field has been directed towards all epitaxial GaAs-based structures by employing novel active materials. LÄS MER

5. 19. Synthesis and Characterization of ZnO Nanostructures

   Författare :Li Li Yang; Qingxiang Zhao; Magnus Willander; Jinghai Yang; Noel Magnea; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Zinc oxide; nanostructures; heterostructures; controllable growth; optical properties; postannealing; diffusion coefficient; Semiconductor physics; Halvledarfysik;

   Sammanfattning : One-dimensional ZnO nanostructures have great potential applications in the fields of optoelectronic and sensor devices.  Therefore, it is very important to realize the controllable growth of one-dimensional ZnO nanostructures and investigate their properties. LÄS MER

7. 20. Quantitative Modeling of Gain in Quantum Cascade Lasers under Operational Intensities

   Författare :David Winge; Matematisk fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; non-linear response; quantum cascade lasers; modelling; Non-equilibrium Green s functions; Gain clamping; Fysicumarkivet A:2016:Winge; kvantkaskadlaser; terahertz; infrarött; Halvledarfysik; spektroskopi; simulering;

   Sammanfattning : This thesis adresses modeling of quantum cascade lasers using non-equilibrium Green’s functions. Focus lies on the quantitative modeling of the gain when the systems are exposed to strong laser fields, as under realistic opertional conditions. LÄS MER