Sökning: "High peak-to-valley ratio"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden High peak-to-valley ratio.

  1. 1. 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

  3. 2. On-line Mobile in situ Gamma Spectrometry

    Författare :Thomas Hjerpe; Lund Medicinsk strålningsfysik; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; radiobiologi; Kärnfysik; Nuclear physics; radiation protection.; 137Cs; peak-to-valley method; depth distribution; orphan source search; orphan sources; emergency preparedness; mobile gamma spectrometry; nuclear accidents; Nuclear medicine; radiobiology; Nukleärmedicin;

    Sammanfattning : Mobile in situ gamma spectrometry is an important instrument in the emergency preparedness for nuclear accidents. This work contributes through the development of strategies and analysis methods for two applications: an on-line search for gamma-emitting orphan sources and on-line estimation of the depth distribution of 137Cs. LÄS MER

  4. 3. Tunneling Based Electronic Devices

    Författare :Erik Lind; Institutionen för elektro- och informationsteknik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SiGe; Esaki Diodes; classical mechanics; quantum mechanics; relativity; termodynamik; relativitet; kvantmekanik; statistisk fysik; Matematisk och allmän teoretisk fysik; thermodynamics; gravitation; statistical physics; GaAs; Mathematical and general theoretical physics; Resonant Tunneling Permeable Base Transistors; Resonant Tunneling Diodes; klassisk mekanik; Fysicumarkivet A:2004:Lind;

    Sammanfattning : This thesis concerns different kinds of tunneling based devices all showing negative differential resistance. The thesis is divided in three parts, resonant tunneling transistors, Esaki diodes and coupled zero dimensional systems. LÄS MER

  5. 4. Vertical III-V Semiconductor Devices

    Författare :Tomas Bryllert; Fasta tillståndets fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Halvledarfysik; Semiconductory physics; heterostructure barrier varactor frequency multiplier; field effect transistor; resonant tunneling; artificial molecule; terahertz; nanowire; Quantum dots;

    Sammanfattning : This thesis is based on three projects that deal with vertical III-V semiconductor devices. The work spans over basic research as well as more applied aspects of III-V semiconductor technology. All projects have in common that they rely on advanced epitaxial growth to form the starting material for device fabrication. LÄS MER

  7. 5. Silicon nanogaps: An electronic bridge to the molecular world

    Författare :Jonas Berg; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nanocrystals; TSRAM; Silicon nanogaps; Molecular electronics; Selective etching; Resonant Tunneling Diodes; Molecules;

    Sammanfattning : We have designed and manufactured silicon nanogaps aimed at electrically interfacing molecules, utilizing the precision thickness control in an oxidation process. An insulating layer was formed on a silicon wafer, and then polysilicon was deposited on top. LÄS MER