We review the current work on x-ray phase vortices. We explain the role of an x-ray vortex in phase recovery and speculate on its possible applications in other fields of x-ray optical research. We present our theoretical understanding of the structure of phase vortices and test these predictions against experiment. We present experimental observations of phase vortices with charge greater than...

Ionic liquid surfaces can become electrically charged during X-ray photoelectron spectroscopy experiments, due to the flux of photoelectrons leaving the surface. This causes a shift in the measured binding energies of X-ray photoelectron peaks that depends on the magnitude of the surface charging. Consequently, a charge correction method is required for ionic liquids. Here we demonstrate the na...

We use time-resolved optical reflectivity and x-ray diffraction with femtosecond resolution to study the dynamics of the structural order parameter of the charge density wave phase in TiSe2. We find that the energy density required to melt the charge density wave nonthermally is substantially lower than that required for thermal suppression and is comparable to the charge density wave condensat...

The cosmic X-ray background (XRB) is largely due to accretion onto supermassive black holes integrated over cosmic time. Thus, extragalactic X-ray surveys offer the potential to contribute substantially to our understanding of the physics of Active Galactic Nuclei (AGN) as well as the evolution of the AGN population. Such surveys have dramatically advanced over the past four years, largely due ...

Scanning transmission X-ray microscopy was used to chemically image RuO(2) nano-layer coated multi-walled carbon nanotubes (RuO(2)/MWCNT) with a spatial resolution of 30 nm. X-Ray absorption near-edge structure spectroscopy of individual RuO(2)/MWCNTs has been compared with that of MWCNTs and RuO(2) which confirms that RuO(2) interacts with MWCNTs through charge redistribution.

The cosmic X-ray background (XRB) is largely due to accretion onto supermassive black holes integrated over cosmic time. Thus, extragalactic X-ray surveys offer the potential to contribute substantially to our understanding of the physics of Active Galactic Nuclei (AGN) as well as the evolution of the AGN population. Such surveys have dramatically advanced over the past four years, largely due ...

Recent investigations of cosmic ray primaries and secondaries at aviation altitudes in the Earth’s atmosphere include the study of Z≥2 particles along the London-New York flight routes on supersonic aircraft. Preliminary charge spectra will be presented for these nuclei and comparisons will be made with the predictions of cosmic ray transport models in the Earth’s atmosphere.

The electronic ferroelectric lutetium ferrite (LuFe(2)O(4)) was studied by x-ray diffraction as a function of pressure. Pressure is shown to induce an irreversible rhombohedral to orthorhombic transition leading to a supercell determined by the combination of electron and synchrotron x-ray diffraction. This new configuration is proposed to be charge ordered in agreement with the results of resi...

The study of the Verwey transition in magnetite has been a matter of intense study during the last years [1,2]. The mechanism proposed by Verwey [3] was the charge localization and ordering of the electrons at the iron octahedral sites giving rise to an ordered sequence of Fe3þ and Fe2þ ions. Recent x-ray diffraction and resonant x-ray scattering at the iron K edge have strongly modified this d...

The new instrument based on the dispersive optics for the X-ray absorption fine structure (XAFS) was developed at BL-5 of the SR Center. The vertical axis of the synchrotron radiation is used to disperse the X-ray energy in the newly developed instrument, named vertically dispersive XAFS (VDXAFS) instrument. The vertical energy dispersion is achieved using a cylindrical polychromator, and the h...