Sökning: "quantum point contact"

Visar resultat 1 - 5 av 24 avhandlingar innehållade orden quantum point contact.

  1. 1. Noise in quantum point contacts

    Författare :Jan Peter Hessling; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; noise; 1 f-noise; elementary fluctuator; quantum point contact; flicker; two level system; impurity; öow frequency;

    Sammanfattning : .... LÄS MER

  3. 2. Fluctuations in Mesoscopic Constrictions

    Författare :Jan Peter Hessling; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; low frequency; fluctuations; quantum; noise; 1 f-noise; superconductivity; impurity; point contact; Andreev reflection; shot noise;

    Sammanfattning : In normal and superconducting quantum point contacts there are several sources of fluctuations. Thermally activated impurities in the vicinity of the junction cause the current (or voltage) to change with a typical frequency of the order of one Hz up to a few kHz. LÄS MER

  4. 3. Fabrication of Low-Dimensional Structures in III-V Semiconductors

    Författare :Ivan Maximov; Fasta tillståndets fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; III-V semiconductors; plasma; etching; aerosol; lithography; quantum dots; quantum well wires; quantum point contact; damage; luminescence; Fysicumarkivet A:1997:Maximov; Halvledarfysik; Semiconductory physics;

    Sammanfattning : The thesis presents studies on the processing technology and the characterization of nanometer-sized and low-dimensional structures in III-V semiconductors. Two major approaches are described: 1) the combination of aerosol technology and plasma etching for the fabrication of quantum dots (QDs) in InP-based materials and 2) the use of high-resolution electron beam lithography and plasma or wet chemical etching to make quantum well wires (QWWs) in both GaAs and InP-based structures. LÄS MER

  5. 4. Interactions, initial states, and low-dimensional semiconductors

    Författare :Peter Jaksch; Stephanie M. Reimann-Wacker; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Q!uantum mechanical interactions; quantum point contact QPC ; quantum wires; exchange-correlation energy; Reilly model; quantum algorithms; Physics; Fysik;

    Sammanfattning : This thesis is concerned with different aspects of quantum mechanical interactions. The first part of the thesis focuses on their effects in low-dimensional semiconductors; the second part on one of their applications: quantum algorithms, which utilize superpositions created from quantum mechanical interactions. LÄS MER

  7. 5. Collective Electron Dynamics in Mesoscopic Systems

    Författare :Oleksandr Zazunov; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Andreev reflection; Josephson effect; qubit; composite fermions; Andreev levels; resonant tunneling; superconductivity; high-T c superconductors; quantum point contact; fractional quantum Hall effect;

    Sammanfattning : This work is devoted to a theoretical investigation of collective electron dynamics in low dimensional materials and mesoscopic structures. A common feature of these studies is the focus on the properties of the low energy dynamics of conduction electrons. One class of studied materials is the high-Tc superconductor Nd2CuO4 and related compounds. LÄS MER