Sökning: "single quantum-wells"

Visar resultat 1 - 5 av 23 avhandlingar innehållade orden single quantum-wells.

1. 1. Spectroscopic studies of III-V semiconductors in two, one and zero dimensions

   Författare :Dan Hessman; Fasta tillståndets fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; InAs-InP; low-dimensional structures; quantum wells; quantum dots; quantum wires; k.p calculations; type-II; photoluminescence; V grooves; Stranski Krastanow; single dot spectroscopy; GaAs-InP; III-V semiconductors; Fysicumarkivet A:1996:Hessman; InAs-GaAs; GaInAs-InP; Halvledarfysik; InP-GaInP; Semiconductory physics;

   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

3. 2. Zeeman Interaction in Low-Dimensional III-V Semiconductor Structures

   Författare :Bernhard Kowalski; Fasta tillståndets fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; optically detected spin resonance; spin resonance; effective g-value; III-V semiconductors; low-dimensional structures; quantum wells; quantum dots; Stranski-Krastanow; photoluminescence; GaInAs; single dot Magneto-luminescence; Fysicumarkivet A:1997:Kowalski; Halvledarfysik; Semiconductory physics; GaInAs-InP;

   Sammanfattning : The Zeeman interaction in low-dimensional III-V semiconductor nanostructures is studied. The effective g-value of bulk InGaAs is measured by two different spin resonance techniques. Experimental conditions were found to control the Overhauser effect, thus enabling a highly accurate determination of the g-value, g* = -4.070 ± 0. LÄS MER

4. 3. Bose-Einstein Condensation of Magnetic Excitons in Semiconductor Quantum Wells

   Författare :Vitalie Boţan; Lars Nordström; Sveatoslav Moskalenko; Pavlos Lagoudakis; Uppsala universitet; []
   Nyckelord :Physics; Bose-Einstein condensation; magnetic excitons; electron-hole pairs; electron-hole liquid; magnetorotons; magnetoplasmons; superfluidity; Fysik;

   Sammanfattning : In this thesis regimes of quantum degeneracy of electrons and holes in semiconductor quantum wells in a strong magnetic field are studied theoretically. The coherent pairing of electrons and holes results in the formation of Bose-Einstein condensate of magnetic excitons in a single-particle state with wave vector K. LÄS MER

5. 4. Epitaxy of GaAs-based long-wavelength vertical cavity lasers

   Författare :Carl Asplund; KTH; []
   Nyckelord :gainnas; ingaas; quantum wells; movpe; mocvd; vertical cavity laser; bcsel; long-wavelength; epitaxy; xrd; dbr;

   Sammanfattning : Vertical cavity lasers (VCLs) are of great interest aslow-cost, high-performance light sources for fiber-opticcommunication systems. They have a number of advantages overconventional edge-emitting lasers, including low powerconsumption, efficient fiber coupling and wafer scalemanufacturing/testing. LÄS MER

7. 5. Dilute Nitride Lasers and Spectrally Engineered Semiconductor Laser Resonators

   Författare :Göran Adolfsson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; single mode laser; transfer matrix method; threshold current; InGaAs; GaAs; multiple quantum wells; dilute nitrides; two-color laser; GaInNAs; Semiconductor lasers; molecular beam epitaxy; characteristic temperature; temperature dependence; ambipolar diusion; Fabry-Perot resonator; spectral engineering;

   Sammanfattning : The first part of this thesis deals with long wavelength (1.2-1.3 um) InGaAs(N)multiple quantum-well (QW) lasers grown on GaAs, with the aim of understandingand improving their threshold and temperature characteristics. The epitaxialmaterial is grown by molecular beam epitaxy (MBE). LÄS MER