Sökning: "Thermionic emission"

Visar resultat 1 - 5 av 14 avhandlingar innehållade orden Thermionic emission.

1. 1. Thermoelectric phenomena in low-dimensional semiconductor systems

   Författare :Magnus Larsson; Matematisk fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; kvantmekanik; relativitet; gravitation; statistisk fysik; termodynamik; Semiconductory physics; Halvledarfysik; thermopower anomaly; thermoelectricity; thermionic couple; zone-folding; cool chip; ballistic; thermionic; Mathematical and general theoretical physics; Matematisk och allmän teoretisk fysik; thermodynamics; statistical physics; relativity; quantum mechanics; klassisk mekanik; classical mechanics;

   Sammanfattning : This thesis investigates thermoelectric effects, predominantly in low-dimensional semiconductors. Various novel phenomena are predicted, investigated and discussed. LÄS MER

3. 2. Thermal Properties of Clusters and Molecules - Experiments on Evaporation, Thermionic Emission, and Radiative Cooling

   Författare :Erika Sundén; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; water clusters fullerenes unimolecular decay evaporation thermionic emission radiative decay cooling rates heat capacities;

   Sammanfattning : This thesis presents experiments performed on clusters and molecules, where the three channels of unimolecular decay have been studied. Evaporation from protonated and negatively charged water cluster have yielded size dependent heat capacities, where the smallest sizes with fewer than $21$ molecules show a heat capacity similar to bulk ice whereas clusters with molecules between $21$ and $300$ have a heat capacity in between that of ice and liquid water. LÄS MER

4. 3. Numerical modelling of hot electron transport in Schottky-diodes and heterojunction structures

   Författare :Hans Hjelmgren; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; n-GaAs; ; energy balance equations; dc-properties;

   Sammanfattning : A one-dimensional drift-diffusion model, including energy balance equations, is used to model Schottky-diodes and heterojunction structures. The set of equations are solved simultaneously with a finite-difference iterative scheme. LÄS MER

5. 4. Vertical III-V Nanowire Transistors for Low-Power Electronics

   Författare :Abinaya Krishnaraja; Nanoelektronik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; metal-oxide-semiconductor field-effect transistor MOSFET ; Steep slope; Tunnel Field-Effect Transistors; Vertical nanowire; III-V materials; semiconducting III-V; InAs; GaSb; InGaAsSb; PMOS; Transistor; Electronics;

   Sammanfattning : Power dissipation has been the major challenge in the downscaling of transistor technology. Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) have struggled to keep a low power consumption while still maintaining a high performance due to the low carrier mobilities of Si but also due to their inherent minimum inverse subthreshold slope (S ≥ 60 mV/dec) which is limited by thermionic emission. LÄS MER

7. 5. Carrier dynamics in blue and green InGaN LED structures

   Författare :Rinat Yapparov; Saulius Marcinkevičius; Ulrich Theodor Schwarz; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; InGaN quantum wells; interwell transport; near-field scanning optical microscopy; internal quantum efficiency; V-defects; InGaN-kvantbrunnar; transport mellan brunnar; optisk mikroskopi med närafältsskanning; intern kvanteffektivitet; V-defekter; Physics; Fysik; Optics and Photonics; Optik och fotonik;

   Sammanfattning : This thesis focuses on effects that are critical to achieving high internal quantum efficiency (IQE) in GaN-based light-emitting diodes (LEDs) that emit in a broad spectral range, from violet to green-yellow. These effects include interwell carrier transport in multiple quantum well (QW) structures, lateral transport in the QW plane, and radiative and nonradiative recombination. LÄS MER