• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 30
  • 18
  • Tagged with
  • 48
  • 48
  • 41
  • 35
  • 22
  • 21
  • 20
  • 18
  • 18
  • 17
  • 15
  • 14
  • 13
  • 12
  • 11
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Characterization of the electronic properties of LaIrIn5: calculations, transport-, heat capacity- and de Haas-van Alphen-experiments / Bestimmung der elektronischen Eigenschaften von LaIrIn5: Rechnungen, Transport-, Wärmekapazitäts- und de Haas-van Alphen-Experimente

Forzani, Eugenio Angelo 12 January 2007 (has links)
No description available.
42

Dimensionseffekte in Halbleiternanodrähten / Dimensional Effects in Semiconductor Nanowires

Stichtenoth, Daniel 23 June 2008 (has links)
No description available.
43

Untersuchung der lokalen strukturellen und elektronischen Eigenschaften von Fe-GaAs Schottky-Kontakten mit atomar aufgelöster Raster-Tunnel-Mikroskopie in Querschnittsgeometrie / Investigation of the structural and local electronic properties of Fe-GaAs Schottky contacts with atomically resolved Scanning Tunneling Microscopy in Cross-sectional configuration

Winking, Lars-Helge 29 January 2009 (has links)
No description available.
44

Scale-free Fluctuations in in Bose-Einstein Condensates, Quantum Dots and Music Rhythms / Skalenfreie Fluktuationen in Bose-Einstein Kondensaten, Quantenpunkten und Musikrhythmen

Hennig, Holger 27 May 2009 (has links)
No description available.
45

Korngrenzsegregation in Silber-Nickel und Kupfer-Wismut Legierungen / Grain Boundary Segregation in Silver-Nickel and Copper-Bismuth Alloys

Wolde-Giorgis, Daniel 25 August 2005 (has links)
No description available.
46

Ultrafast Photon Management: The Power of Harmonic Nanocrystals in Nonlinear Spectroscopy and Beyond

Kijatkin, Christian 01 April 2019 (has links)
The present work broaches the physics of light-matter interaction, chiefly using nonlinear optical spectroscopy in a newly developed framework termed as Photon Management Concept. This way, existing fragments dealing with specific properties of harmonic and upconversion nanoparticles (HNPs/UCNPs) are consolidated into a full and coherent picture with the primary goal of understanding the underlying physical processes and their impact on the application side, especially in terms of imaging techniques, via suitable experimental and numerical studies. Contemporary optical setups involving contrast-enhancing agents are frequently limited in their excitation and detection configurations owing to a specialization to a select number of markers. As a result, the bandwidth of experimental methods and specimens that may be investigated is severely restricted in a large number of state-of-the-art setups. Here, an alternative approach involving HNPs and UCNPs, respectively, is presented providing an overview from their synthesis to optical characterization and to potential fields of application. Based on their inherent flexibility based on their nonlinear optical response, especially in terms of wavelength and intensity tunability, the PMC alleviates prevalent limitations by dynamically adapting the setup to a sample instead of the preliminary culling to a reduced number of eligible specimens that must not change their optical properties significantly during investigation. The use of HNPs supersedes such concerns due to their nearly instantaneously generated, strongly anti-Stokes shifted, coherent emission capable of producing radiation throughout the visible spectral range, including infrared and ultraviolet wavelengths. This way, HNPs transcend the traditional field of imaging and introduces potential applications in optomanipulation or holographic techniques. Thorough (nonlinear) optical characterization of UCNPs and alkali niobate HNP ensembles is performed to assess the fundamental physical mechanisms interwoven with numerical studies leading to their wide-ranging applicability. Final remarks show that HNPs are ideal candidates for realization of the PMC and yet hold an even further potential beyond current prospects.
47

Ab-initio-Untersuchungen von Oberflächen- und Bulksystemen

Greuling, Andreas 21 December 2010 (has links)
In dieser Arbeit setzen wir ab-initio-Methoden zur Untersuchung einiger Oberflächensysteme und eines Bulksystems ein. Im Wesentlichen greifen wir hierbei auf die Dichtefunktionaltheorie (DFT) und die GW-Approximation (GWA) im Rahmen der Vielteilchenstörungstheorie zurück. Wir nutzen diese Methoden um die Adsorption von TMA auf der Rutil TiO2-Oberfläche zu untersuchen, optische Spektren von TiO2 zu berechnen und um die Adsorption von [7]-HCA auf der Calcit(10-14)-Oberfläche zu verstehen. Weiterhin beschäftigen wir uns intensiv mit PTCDA auf Ag(111), welches mit einer chemisch kontaktierten STM-Spitze manipuliert wird.
48

Structural and optical impact of transition metal implantation into zinc oxide single crystals and nanowires / Strukturelle und optische Auswirkungen derÜbergangsmetallimplantation in ZnO Einkristalle und Nanodrähte

Müller, Sven 30 March 2009 (has links)
No description available.

Page generated in 0.0787 seconds