Sökning: "quantum dot"

Visar resultat 11 - 15 av 129 avhandlingar innehållade orden quantum dot.

1. 11. Quantum technologies for secure communications

   Författare :Junior Ricardo Gonzales Ureta; Ana Predojević; Matthias Kleinmann; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum Optics; Quantum Information; fysik; Physics;

   Sammanfattning : Quantum technologies promise to revolutionize a variety of fields such as metrology, cryptography or computing, among others. The resources that quantum mechanics offers allow us to design faster optimization algorithms, to provide unconditional security in communications and to measure quantities beyond the grasp of current technology. LÄS MER

3. 12. 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. 13. Thermoelectric Phenomena in Quantum Dots

   Författare :Sofia Fahlvik Svensson; Fasta tillståndets fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fysicumarkivet A:2014:Fahlvik Svensson; Coulomb blockade; nanowire; thermoelectricity; quantum dot;

   Sammanfattning : Thermoelectricity is being intensively researched as it is believed to hold great promise for applications in power generation and cooling. One way to quantify the electrical power output of a thermoelectric material is the power factor, a function of electrical conductivity and thermopower. LÄS MER

5. 14. Resonant Tunneling in Laterally Confined Quantum Structures

   Författare :Boel Gustafson; Fasta tillståndets fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; gravitation; relativity; quantum mechanics; classical mechanics; Mathematical and general theoretical physics; Fysik; Physics; High peak-to-valley ratio; Lateral confinement; Quantum dots; Resonant tunneling; Self-assembled quantum dots; Schottky depletion; Buried metal gate; Electron transport; Magnetic-field dependence; Energy level width; Tunneling transistors; Mode coupling; statistical physics; thermodynamics; Matematisk och allmän teoretisk fysik; klassisk mekanik; kvantmekanik; relativitet; statistisk fysik; termodynamik; Technological sciences; Teknik; Fysicumarkivet A:2001:Gustafson;

   Sammanfattning : In the thesis, three-dimensionally confined resonant tunneling structures were studied experimentally. Two approaches were used for obtaining quantum confinement: gate-defined lateral constriction of double barrier structures, and epitaxial growth of self-assembled quantum dots. LÄS MER

7. 15. 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