Sökning: "Quantum wires"

Visar resultat 1 - 5 av 31 avhandlingar innehållade orden Quantum wires.

1. 1. Quantum and Ballistic Nanodevices

   Författare :Ivan Shorubalko; Fasta tillståndets fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; III-V semiconductors; low-dimensional structures; nanostructures; ballistic rectifiers; three-terminal ballistic junctions; quantum wires; planar quantum dots; logic gates; harmonic generation; InP; GaInAs; nanoelectronics; Fysik; Physics; nonlinear transport; electron transport; quantum nanodevices; ballistic nanodevices; Fysicumarkivet A:2003:Shorubalko;

   Sammanfattning : In this thesis, electron transport in quantum and ballistic devices was studied. The devices studied here were quantum wires, planar quantum dots, ballistic rectifiers, artificial functional materials, and three-terminal ballistic junctions. The possible application of such devices in the future nanoelectronics was also investigated. LÄS MER

3. 2. Quantum optics in constrained geometries

   Författare :Björn Hessmo; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum chemistry; quantum optics; atom optics; complementarity; magnetic traps; laser cooling; quantum information; quantal phases; Kvantkemi; Quantum chemistry; Kvantkemi; Quantum Chemistry; kvantkemi;

   Sammanfattning : When light exhibits particle properties, and when matter exhibits wave properties quantum mechanics is needed to describe physical phenomena. A two-photon source produces nonmaximally entangled photon pairs when the source is small enough to diffract light. It is shown that diffraction degrades the entanglement. LÄS MER

4. 3. Modelling of Quantum Transport in Nanostructures

   Författare :Dan Csontos; Fasta tillståndets fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ballistic transport; quantum wire; quantum dot; resonant tunnelling; three-terminal; disorder; Physics; Fysik; Fysicumarkivet A:2002:Csontos; scattering matrix; quantum transport;

   Sammanfattning : In this thesis, theoretical studies of the transport properties of three nanoscale systems: one-dimensional (1D) quantum wires (QWRs), zero-dimensional (0D), laterally confined, double-barrier resonant tunnelling structures (DBRTSs) and three-terminal ballistic junctions (TBJs), have been performed. In the first part of the thesis, an overview of the realization and properties of such systems is given along with a description of modelling tools used in the calculations. LÄS MER

5. 4. Cathodoluminescence Studies of Quantum Structures and III-V nitrides

   Författare :Anders Petersson; Fasta tillståndets fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; AlGaN; Fysik; Physics; GaN-AlGaN; single dot spectroscopy; InP-GaInP; Stranski Krastanow; quantum dots; quantum wires; low-dimensional structures; InAs-GaAs; III-V nitride; Cathodoluminescence; III-V semiconductors; Fysicumarkivet A:1999:Petersson;

   Sammanfattning : Characterization of low-dimensional semiconductor structures is a challenging task. The thesis is based on experiments, using cathodoluminescence (CL) as a tool for characterization. The high spatial resolution and the possibility of spectroscopy of small structures make CL one of the most powerful techniques for these types of investigations. LÄS MER

7. 5. 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