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Visar resultat 1 - 5 av 41 avhandlingar som matchar ovanstående sökkriterier.
1. Spectroscopic studies of III-V semiconductors in two, one and zero dimensions
Sammanfattning : In this thesis, spectroscopic studies of quantum wells (QWs), quantum wires (QWRs) and quantum dots (QDs) in III-V semiconductors are presented. The electronic structure of these low-dimensional structures have been studied by absorption, photocurrent, electroreflectance, photoluminescence (PL), and photoluminescence excitation (PLE) spectroscopy. LÄS MER
2. Gallium arsenide based buried heterostructure laser diodes with aluminium-free semi-insulating materials regrowth
Sammanfattning : Semiconductor lasers based on gallium arsenide and relatedmaterials are widely used in applications such as opticalcommunication systems, sensing, compact disc players, distancemeasurement, etc. The performance of these lasers can beimproved using a buried heterostructure offering lateralcarrier and optical confinement. LÄS MER
3. Tunneling Based Electronic Devices
Sammanfattning : This thesis concerns different kinds of tunneling based devices all showing negative differential resistance. The thesis is divided in three parts, resonant tunneling transistors, Esaki diodes and coupled zero dimensional systems. LÄS MER
4. Linear and Nonlinear Transport in Quantum Nanostructures
Sammanfattning : In this thesis, electron transport in mesoscopic semiconductor nanostructures, in particular so-called electron billiards or quantum dots, is studied. The thesis can be divided into two areas: the linear response regime of transport, and the nonlinear response regime of transport. LÄS MER
5. Nanoelectronic Devices Based on Low-Dimensional Semiconductor Structures
Sammanfattning : The present thesis reports on results from the fabrication technology development and the corresponding electrical transport measurements of low-dimensional semiconductor structures. The focus of the work has been directed towards two parts: the ballistic transport in nanostructure devices at room temperature, and the development of a charge-sensing technique for quantum dots (QD) in nanowires. LÄS MER