Sökning: "quantum coherent electron transport"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden quantum coherent electron transport.

  1. 1. 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

  2. 2. Quantum Transport Theory in Graphene

    Författare :Anders Bergvall; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; quantum coherent electron transport; nanoribbons; FT-LDOS; grain boundaries; tight-binding; graphene;

    Sammanfattning : In this thesis, we focus on different aspects of electron transport in nanostructured graphene (such as graphene nanoribbons). Wedevelop and implement numerical methods to study quantum coherent electron transport on an atomistic level, complemented by analytical calculations based on the Dirac approximation valid close to the points $\vec{K}$ and $\vec{K}^\prime$ in the graphene Brillouin zone. LÄS MER

  3. 3. Transport Studies of Local-Gate Defined Quantum Dots in Nanowires

    Författare :Carina Fasth; Fasta tillståndets fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Semiconductory physics; Fysik; Physics; quantum devices; nanowire; quantum dot; Halvledarfysik;

    Sammanfattning : This thesis focuses on electrical transport in semiconductor InAs nanowires grown by chemical beam epitaxy. Initially, transport length scales of homogeneous InAs n-type nanowires are characterized by low-temperature magnetoconductance measurements. The measurements show phase-coherent conductivity corrections. LÄS MER

  4. 4. Transport phenomena in quantum wells and wires in presence of disorder and interactions

    Författare :Valeria Vettchinkina; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; time-dependent density-functional theory; disorder; electron correlation; Lowdimensional semiconducting systems; transport phenomena; Fysicumarkivet F:2012:Vettchinkina;

    Sammanfattning : Present-day electronics employ circuits of smaller and smaller dimensions, and today the length scales are so small that the laws of physics which rule micro-cosmos, quantum mechanics, become directly important. This thesis reports on theoretical work on electron transport in different nanostructures. LÄS MER

  5. 5. Theoretical Studies of Electron Transport in Quantum Dot Structures

    Författare :Carina Fasth; Fasta tillståndets fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : We calculate the phase property of the reflection coefficient in two-terminal structures using a lattice tight-binding model. It is seen that, provided that there exist two coherent reflection paths, the reflection probability can be zero for certain electron energies. LÄS MER