• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 308
  • 71
  • 12
  • 8
  • 2
  • 1
  • 1
  • Tagged with
  • 402
  • 273
  • 171
  • 158
  • 156
  • 156
  • 107
  • 76
  • 50
  • 45
  • 43
  • 41
  • 41
  • 41
  • 30
  • 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.
1

Ellipsometric studies of SiC in the infrared, visual and ultraviolet spectral region /

Lindquist, O. P. Alexander, January 2003 (has links) (PDF)
Diss. (sammanfattning) Linköping : Univ., 2003. / Härtill 6 uppsatser.
2

Rare Earth elements in optical materials and design of high power ytterbium fiber laser for frequency doubling using nonlinear ppKTP crystal.

Rydberg, Sara January 2010 (has links)
No description available.
3

Studies of Nanostructured Layers with UV-VIS Spectroscopic Ellipsometry

Mocking, Tijs January 2008 (has links)
In this report a model analysis is presented for three different nanostructured layers: silicon nanotips (SiNTs), gold nanosandwiches and Split Ring Resonators (SRR). The last two materials are metamaterials and both may show a negative refraction index. Experimental data are obtained for every sample using a variable angle spectroscopic ellipsometer. For the gold nanosandwiches, also an infrared ellipsometric measurement is done. For complex layers like these, advanced modeling is necessary. A recently developed analysis program including options for both anisotropic permittivity and permeability is used. A realistic model is presented in this report for the gold nanosandwiches, which also includes the magnetic activity in the layer itself. The results for the nanosandwiches are reasonable, and a magnetic oscillation is found in the horizontal plane at around 260 nm although it was not expected to have a resonance that far in the UV-range. For the SiNTs and the SRR it was not possible to create an acceptable model.
4

Studies of Nanostructured Layers with UV-VIS Spectroscopic Ellipsometry

Mocking, Tijs January 2008 (has links)
<p>In this report a model analysis is presented for three different nanostructured layers: silicon nanotips (SiNTs), gold nanosandwiches and Split Ring Resonators (SRR). The last two materials are metamaterials and both may show a negative refraction index. Experimental data are obtained for every sample using a variable angle spectroscopic ellipsometer. For the gold nanosandwiches, also an infrared ellipsometric measurement is done. For complex layers like these, advanced modeling is necessary. A recently developed analysis program including options for both anisotropic permittivity and permeability is used. A realistic model is presented in this report for the gold nanosandwiches, which also includes the magnetic activity in the layer itself. The results for the nanosandwiches are reasonable, and a magnetic oscillation is found in the horizontal plane at around 260 nm although it was not expected to have a resonance that far in the UV-range. For the SiNTs and the SRR it was not possible to create an acceptable model.</p>
5

Silicon Based Photonic Devices and Their Applications

Li, Qiang January 2011 (has links)
The integration of modern electronic devices for information processing is rapidly ap-proaching an interconnect bottleneck. Silicon photonics can be a promising solution forcircumventing this bottleneck, as already being anticipated by many electronics manu-facturers including HP, IBM and Intel. In particular, optical interconnects can expeditedata transfer both between and within microchips. This thesis aims at two basic buildingblocks of silicon photonics: waveguides and resonators and addresses their applications inoptical signal processing and their potential integration with plasmonic devices. Firstly, the basic theories of waveguide and resonator are introduced. For a singleresonator which acts as a basic signal processing unit, the transmission, phase shift andgroup delay exhibit unique characteristics. Mode splitting is observed in both a singleresonator and a coupled-resonator system. By tuning the configuration of the coupled-resonator system, one can obtain different transmission characteristics for more advancedsignal processing. Secondly, the fabrication and characterization of silicon waveguides and resonatorsused in the thesis are introduced. The fabrication is carried out with e-beam lithographyfollowed by inductively coupled plasma etching. A vertical grating coupling method isadopted to characterize the transmission spectrum. Thirdly, based on a single-ring resonator, three kinds of signal processing are ex-perimentally demonstrated: (1) 10 Gb/s format conversion from non-return-to-zero toalternate-mark-inversion signal; (2) a microwave photonic phase shifter providing a tun-able phase shift of 0–4.6 rad for a 20 GHz signal; (3) a delay line providing maximaldelay times of 80 ps, 95 ps, 110 ps and 65 ps, respectively, for signals in return-to-zero,carrier-suppressed return-to-zero, return-to-zero duobinary, and return-to-zero alternate-mark-inversion formats. Fourthly, based on a single-ring resonator with mode-splitting, two kinds of signalprocessing are experimentally demonstrated: (1) a dense wavelength conversion using thefree carrier dispersion effect with a data rate ranging from 500 Mb/s to 5 Gb/s; (2) amaximum pulse advancement of 130 ps for a 1 ns signal pulse. Since silicon photonic devices are limited by diffraction limit, we further look intotheir hybridization with the diffraction-limit-free plasmonic devices. Two directional cou-plers from a Si photonic waveguide to a hybrid Si-metal plasmonic waveguide and to ametal-insulator-metal plasmonic waveguide are investigated. The proposed hybrid cou-plers feature a short coupling length, a high coupling efficiency, a high extinction ratioand a low insertion loss. / QC 20110315
6

New methodology for optical sensing and analysis /

Bakker, Jimmy, January 2004 (has links)
Lic.-avh. Linköping : Univ., 2004.
7

Optical absorption and electrical conductivity in lithium intercalated amorphous tungsten oxide films /

Berggren, Lars, January 2004 (has links)
Diss. (sammanfattning) Uppsala : Univ., 2004. / Härtill 6 uppsatser.
8

Near-infrared photodetectors based on Si/SiGe nanostructures /

Elfving, Anders, January 2006 (has links)
Diss. (sammanfattning) Linköping : Linköpings universitet, 2006. / Härtill 7 uppsatser.
9

Measuring corneal topography using wavefront analysis technique

Korablinova, Nina. January 2004 (has links)
Heidelberg, Univ., Diss., 2004.
10

Entwurf und Aufbau mikrooptischer Systeme für die Mess- und Übertragungstechnik

Klug, Róbert. January 1900 (has links) (PDF)
Mannheim, Univ., Diss., 2002. / Computerdatei im Fernzugriff.

Page generated in 0.0228 seconds