Sökning: "Mattias Hammar"
Visar resultat 1 - 5 av 11 avhandlingar innehållade orden Mattias Hammar.
1. Type-II interband quantum dot photodetectors
Sammanfattning : Photon detectors based on single-crystalline materials are of great interest for high performance imaging applications due to their low noise and fast response. The major detector materials for sensing in the long-wavelength infrared (LWIR) band (8-14 µm) are currently HgCdTe (MCT) and AlGaAs/GaAs quantum wells (QW) used in intraband-based quantum-well infrared photodetectors (QWIPs). LÄS MER
2. Growth and characterisation of InGaAs-based quantum dots-in-a-well infrared photodetectors
Sammanfattning : This thesis presents results from the development of quantum dot (QD) based infrared photodetectors (IPs). The studies include epitaxial growth of QDs, investigations of the structural, optical and electronic properties of QD-based material as well as characterisation of the resulting components. LÄS MER
3. Design and fabrication of long wavelength vertical cavity lasers on GaAs substrates
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
4. Förtröstans hermeneutik : Nathan Söderbloms lutheranvändning och traditionsbearbetningens problematik
Sammanfattning : Sayings about Christian tradition and its connection to the surrounding community and culture are in a higher degree made invisible in Swedish society today. This is due to a continuing move of secularization but also to the development of other understandings of tradition within a pluralistic society. LÄS MER
5. Compound semiconductor materials and processing technologies for photonic devices and photonics integration
Sammanfattning : The advancement of semiconductor optoelectronics relies extensively on materials and processing technologies of ever-increasing sophistication, such as nanometer-range lithography, epitaxial growth methods with monatomic layer control, and anisotropic etching procedures that allows for the precise sculpturing of device features even in the limit of extreme aspect ratios. However, upcoming application needs puts requirements on optimized designs or device performances, e. LÄS MER