• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 88
  • 42
  • 24
  • 23
  • 6
  • 6
  • 6
  • 3
  • 3
  • 1
  • 1
  • Tagged with
  • 242
  • 242
  • 62
  • 59
  • 55
  • 40
  • 39
  • 35
  • 35
  • 32
  • 27
  • 27
  • 26
  • 26
  • 25
  • 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.
81

Optical Characterization of Liquids: Refractive Index and Raman Gain Coefficient Measurements

Lopez-Zelaya, Cesar A 01 January 2023 (has links) (PDF)
Novel technologies capable of generating wavelengths not accessible with typical laser gain media have been among the primary drivers of the field of nonlinear optics. Here, we are interested in the linear and nonlinear properties of liquids beyond the visible spectrum, motivated in part by their use as core materials in optical fibers. Given their dispersion, nonlinearities, transparency, and ability to be mixed, liquids show potential for exploiting in-fiber nonlinear phenomena for developing the new generation of low cost, size, weight, and power wavelength-agile fiber-laser sources. For the design, modeling, and experimental realization of these liquid-core fiber laser sources, proper knowledge of dispersion and Raman gain coefficients is necessary. However, the data for the liquids in the near-IR spectrum are sparse, with most reported values being in the visible and only for commonly used solvents. In this thesis, we report a Rayleigh interferometry-based refractometer to characterize the refractive index of 26 solvents relative to standard materials at seven different wavelengths (543.5, 632.8, 780, 973, 1064, 1550, and 1970 nm) at a temperature of ~ 21.3±0.6 °C. The corresponding Sellmeier equations fitted to our data for each liquid are given and compared with previously published literature; percent transmittance data for each liquid are also provided. Furthermore, we use a well-known technique for obtaining the relative total differential Raman cross-section of eight selected solvents at 532 nm. By measuring and analyzing the solvents' spontaneous Raman emission, we obtain their depolarization ratios, linewidth, and calculate their Raman gain coefficients. With knowledge of the electronic resonance and frequency dependence of the total differential cross-section, extrapolations were used to provide values for the total differential cross-section and gain coefficient at 1064 nm.
82

Fragility, melt/glass homogenization, self-organization in chalcogenide alloy systems

Gunasekera, Kapila January 2013 (has links)
No description available.
83

Topological origin of glass formation, rigidity and stress transitions, conductivity and fragility in specially homogeneous Heavy Metal Oxide and Chalcogenide systems

Chakraborty, Shibalik 17 October 2014 (has links)
No description available.
84

Aging of Selenium glass probed by MDSC and Raman Scattering Experiments: Growth of inter-chain structural correlations leading to network compaction

Dash, Shreeram J. 15 June 2017 (has links)
No description available.
85

Laser Spectroscopy Sensor for Measurements of Trace Gaseous Sulfur Dioxide (SO<sub>2</sub>)

Matta, Anand 17 December 2008 (has links)
No description available.
86

Trace Analysis of Biological Compounds by Surface Enhanced Raman Scattering (SERS) Spectroscopy

Boddu, Naresh K. 17 December 2008 (has links)
No description available.
87

Fabrication and Characterization of Substrate Materials for Trace Analytical Measurements by Surface Enhanced Raman Scattering (SERS) Spectroscopy Technique

Vabbilisetty, Pratima January 2008 (has links)
No description available.
88

CARS Thermometry Studies of Plasma Assisted Combustion in Ethylene-Air and Hydrogen-Air Mixtures and of a Dielectric Barrier Discharge Actuator

Zuzeek, Yvette 30 July 2010 (has links)
No description available.
89

Surface- and point-defect-related Raman scattering in wurtzite semiconductors excited above the band gap

Kranert, Christian, Schmidt-Grund, Rüdiger, Grundmann, Marius 02 August 2022 (has links)
We present a model for exciton-mediated first-order Raman scattering by longitudinal optical phonons in the presence of surfaces and point defects. It is consistent with the experimental data for all wurtzite structure materials investigated and reviewed here (GaN, InN, ZnO and CdS) and also explains not yet understood observations in the literature. We distinguish between the involvement of elastic scattering by the surface and by point defects in the scattering process. Surface scattering causes the dependence of the line position on the crystal orientation of the excited surface in pure crystals. Point defect scattering is independent of the crystal orientation and appears as an additional contribution in defect-rich crystals. We postulate the polarization properties of these distinct processes which are in good agreement with the experiments and allow us to identify and separate the contributions of these two effects from the polarized spectra.
90

Correlating Melt Dynamics with Glass Topological Phases in Especially Homogenized Equimolar GexAsxS100-2x Glasses using Raman Scattering, Modulated- Differential Scanning Calorimetry and Volumetric Experiments

Almutairi, Badriah Saad 27 September 2020 (has links)
No description available.

Page generated in 0.0813 seconds