Sökning: "InGaAs"

Visar resultat 21 - 25 av 74 avhandlingar innehållade ordet InGaAs.

  1. 21. 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

  2. 22. Spectroscopic studies of InGaAs/GaAs/A1GaAs quantum dots and wires

    Författare :Fredrik Karlsson; Manfred Bayer; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : It is demonstrated that the photoluminescence (PL) spectra of single selfassembled lnAs/GaAs quantum dots (QDs) are very sensitive to excitation energy and crystal temperature, which is explained in terms of modulation of the effective diffusivity of the photogenerated carriers affecting the capture probability into theQD. This effect results in a population of the QD with excess electrons, and can be used as a simple tool to create and study charged exciton complexes. LÄS MER

  3. 23. Linear and Nonlinear Transport in Quantum Nanostructures

    Författare :Anneli Löfgren; Fasta tillståndets fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magnetoconductance; mesoscopic; electron billiard; quantum dot; quantum ratchets; non-linear; symmetries; non-symmetric conduction; rectification; artificial material; Halvledarfysik; Fysicumarkivet A:2002:Löfgren; ballistic transport; quantum transport; 2DEG; Semiconductory physics; InP InGaAs; GaAs AlGaAs;

    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

  4. 24. Nanoelectronic Devices Based on Low-Dimensional Semiconductor Structures

    Författare :Daniel Wallin; Fasta tillståndets fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; InGaAs InP; GaAs AlGaAs; ballistic transport; quantum transport; low-dimensional structures; two-dimensional electron gas; quantum dot; three terminal ballistic junction; nanowire;

    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

  5. 25. Electronic structure and optical properties of InGaAs and InAsP semiconductor quantum wires

    Författare :Johan Hammersberg; Jörn M. Hvam; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : In recent years intensive studies of semiconductor nanostructures or so-called semiconductor quantum structures have been performed in many research groups around the world. The research interest in quantum structures arises both from their potential to expose new physical phenomena in condensed matter physics, allied with fundamental quantum mechanical effects, and from their potential application in electronic and optoelectronic devices. LÄS MER