Sökning: "two dimensional electron gas"

Visar resultat 21 - 25 av 56 avhandlingar innehållade orden two dimensional electron gas.

1. 21. Growth and characterization of SiC and GaN

   Författare :Rafal Ciechonski; Erik Janzén; Sebastian Lourdudoss; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SiC; GaN; Deep level transient spectroscopy; Minority Carrier Transient Spectroscopy; Hall effect; Cathodoluminescence; Scanning electron microscopy; Atomic Force microscopy; sublimation growth; MOCVD; heterostructures; High Electron Mobility transistor; point defects; Material physics with surface physics; Materialfysik med ytfysik;

   Sammanfattning : At present, focus of the SiC crystal growth development is on improving the crystalline quality without polytype inclusions, micropipes and the occurrence of extended defects. The purity of the grown material, as well as intentional doping must be well controlled and the processes understood. LÄS MER

3. 22. Coherent Far-Infrared Mode Pumping in Ballistic Electron Channels

   Författare :Ola Tageman; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The influence of a high frequency electromagnetic field on transport properties of ballistic electron channels is investigated theoretically. We are primarily concerned with submicron-width channels formed by split-gate depletion of a two-dimensional electron gas at a GaAs/AlGaAs heterostructure interface. LÄS MER

4. 23. Study of Non-metallic Inclusion in Alloy 825

   Författare :Hans Kellner; Andrey Karasev; Pär Jönsson; Guozhu Ye; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Alloy 825; FeTi70R alloy; non-metallic inclusions; inclusion distribution; clusters; electromagnetic and gas stirring; ladle treatment; electrolytic extraction; stirring directions; Alloy 825; FeTi70R legering; icke-metalliska inneslutningar; inneslutnings fördelning; kluster; elektromagnetisk och gas omrörning; skänkugnsbehandling; elektrolytisk extraktion; omrörningshåll; Metallurgical process science; Metallurgisk processvetenskap; Steel Forming and Surface Engineering;

   Sammanfattning : It is well known that inclusions affect the properties of steels and alloys. Therefore, it is important to understand what type of inclusions that exist and how they behave and especially with a focus on large size inclusions. LÄS MER

5. 24. Reactions on nanostructured and microporous surfaces

   Författare :Anna Clemens; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Cu-CHA; XRD; solid-state ion-exchange; materials characterisation; electron microscopy; NH3-SCR; zeolites; catalysis; nanostructured graphite; Water ice; DRIFTS; XPS; NOx reduction; Cu-SSZ-13; temperature programmed desorption; ultra-high vacuum; intercalation; UV-Vis spectroscopy;

   Sammanfattning : Interactions between surfaces and molecules play a central role in various fields where catalysis is one example. In order to understand different surface processes, physicochemical characterisation of the surface materials and molecules is required. LÄS MER

7. 25. Electron Transport and Collective Modes in Fermi and non-Fermi Liquids

   Författare :Eric Nilsson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Today’s novel materials can display many interesting phases. Two-dimensional materials with strong electron-electron interactions allow the electrons to enter a hydrodynamic regime at intermediate temperatures. LÄS MER