Avancerad sökning

Visar resultat 1 - 5 av 8 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Three-Dimensional Metal-Semiconductor Heterostructures for Device Applications

   Författare :Lars-Erik Wernersson; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Schottky contacts; space-charge spectroscopy; ballistic transport; Coulomb repulsion; electron interference; resonant tunnelling; lateral confinement; heterojunction permeable base transistor; resonant tunnelling diodes; Fysicumarkivet A:1998:Wernersson; Fysik; Physics; resonant tun; epitaxial overgrowth;

   Sammanfattning : Fabrication and characterisation of buried metal contacts in compound semiconductors are demonstrated. The contacts have been investigated due to their usage both as gates in transistors and as active or passive elements in novel devices. LÄS MER

3. 2. 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

4. 3. Millimeter-Wave Radar for Low-Power Applications

   Författare :Sebastian Heunisch; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Gesture Recognition; Material Characterization; Radar; Reflectrometry; Resonant-Tunnelling Diode; Wavelet Generator; Wideband Millimeter-Wave Circuits;

   Sammanfattning : Radar technology has developed rapidly during the last century. Besides its initial use for military, it is nowadays also applied for many civil applications. Improvements in circuit technology make integrated radar sensors possible, allowing a significant reduction of the production cost. LÄS MER

5. 4. Compact and Efficient Millimetre-Wave Circuits for Wideband Applications

   Författare :Lars Ohlsson; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; resonant-tunnelling diode; millimetre-wave spectrum; integrated transmitter; energy-efficiency; compact circuit; dielectric resonator antenna; transistor; wavelet generator; wideband.;

   Sammanfattning : Radio systems, along with the ever increasing processing power provided by computer technology, have altered many aspects of our society over the last century. Various gadgets and integrated electronics are found everywhere nowadays; many of these were science-fiction only a few decades ago. LÄS MER

7. 5. Metal-Organic Complexes at Surfaces

   Författare :Cristina Isvoranu; Synkrotronljusfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; x-ray absorption spectroscopy; x-ray photoelectron spectroscopy; bi-isonicotinic acid; oxalic acid; spin change; gas adsorption; metal-organic complex; iron phthalocyanine; scanning tunneling spectroscopy; resonant photoemission spectroscopy;

   Sammanfattning : The adsorption of different metal-organic complexes at surfaces was investigated by spectroscopic techniques (x-ray photoemission spectroscopy, x-ray absorption spectroscopy, resonant photoemission spectroscopy) and by scanning tunnelling microscopy. The investigation methods are able to provide atomic scale information on the studied systems, which moreover originates from the top-most atomic layers in a sample, meaning that they are surface sensitive techniques. LÄS MER