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dc.contributor.advisorSeidler, Gerald
dc.contributor.authorHoidn, Oliver
dc.date.accessioned2017-10-26T20:53:32Z
dc.date.available2017-10-26T20:53:32Z
dc.date.submitted2017-08
dc.identifier.otherHoidn_washington_0250E_17928.pdf
dc.identifier.urihttp://hdl.handle.net/1773/40674
dc.descriptionThesis (Ph.D.)--University of Washington, 2017-08
dc.description.abstractThis dissertation provides a perspective on the role of x-ray spectroscopy and diffraction diagnostics in experimental studies of warm dense matter (WDM). The primary focus of the work I discuss is the development of techniques to measure the structure and state variables of laboratory-generated WDM with a view towards both phenomenlogy and placing contraints on theoretical models. I present techniques adapted to two experimental venues for WDM studies: large-scale laser plasma facilities and x-ray free electron lasers. My focus is on the latter, in the context of which I have studied a dose enhancement technique that exploits nonlocal heat transport in nanostructured targets and considered several aspects of optimizing x-ray diffraction measurements. This work came into play in beam runs at the Linac Coherent Light Source (LCLS) in which my group performed x-ray diffraction studies of several materials heated to eV-scale temperatures. The results from these experiments include confirmation of the persistence of long-range crystalline order upon heating of metal oxides to tens of eV temperarures on the 40 fs timescale. One material, MgO, additionally manifested a surprising anomalous early onset in delocalization of valence charge density, contradicting predictions of all models based on either ground state electronic structure or (high-energy density) plasma physics. This particular result outlines a future path for studies of ordered insulators heated to temperatures on the order of the band gap. Such experiments will offer strong tests of electronic strucure theory, implementing a scientific approach that sees measurement of real-space charge density via x-ray diffraction (XRD) as a particularly effectve means to constrain density functional theory (DFT)-based modeling of the solid state/plasma transitional regime.
dc.format.mimetypeapplication/pdf
dc.language.isoen_US
dc.rightsCC BY
dc.subject
dc.subjectPhysics
dc.subject.otherPhysics
dc.titleX-ray Spectroscopies of Warm Dense Matter
dc.typeThesis
dc.embargo.termsOpen Access


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