Related papers: Studies on Neon irradiated amorphous carbon using …

The polarization direction of an electromagnetic field changes and eventually reaches a steady state when propagating through a birefringent material with off axis absorption or gain. The steady state orientation direction depends on the…

We apply a new method "force enhanced atomic refinement" (FEAR) to create a computer model of amorphous silicon (a-Si), based upon the highly precise X-ray diffraction experiments of Laaziri et al. The logic underlying our calculation is to…

We revisit here how Raman spectroscopy can be used to estimate the H content in hard hydrogenated amorphous carbon layers. The H content was varied from 2 at.% to 30 at.%, using heat treatments of a a-C:H, from room temperature to 1300 K…

Cross-sectional transmission electron microscopy (TEM) is used to characterize an amorphous layer observed at the interface in graphite and graphene films grown via thermal decomposition of C-face 4H-SiC. The amorphous layer does not to…

Determining the atomic-level structure of crystalline solids is critically important across a wide array of scientific disciplines. The challenges associated with obtaining samples suitable for single-crystal diffraction, coupled with the…

We review recent progress on the modeling and use of reflection spectra from irradiated and ionized accretion discs. On the computational side, calculations of reflection spectra from discs with non-uniform density structure have shown that…

Aligned interstellar grains produce polarized extinction (observed at wavelengths from the far-ultraviolet to the mid-infrared), and polarized thermal emission (observed at far-infrared and submm wavelengths). The grains must be quite…

Scanning X-ray nanodiffraction microscopy is a powerful technique for spatially resolving nanoscale structural morphologies by diffraction contrast. One of the critical challenges in experimental nanodiffraction data analysis is posed by…

Silicon nanocrystals are produced using a two-stage gold ion implantation technique. First stage implantation using low energy ions leads to the formation of an amorphous Si (a-Si) layer. A subsequent high energy Au irradiation in the…

Here, we report a study on the radiation resistance enhancement of Gd2Zr2O7 nanograin ceramics, in which amorphization, cell volume expansion and multi-stage helium (He) bubble formation are investigated and discussed. Gd2Zr2O7 ceramics…

We present high-resolution spectroscopy of the neon K-shell and iron L-shell interstellar absorption edges in nine X-ray binaries using the High Energy Transmission Grating Spectrometer (HETGS) onboard the Chandra X-ray Observatory. We…

Context: How do molecular clouds form out of the atomic phase? And what are the relative fractions of carbon in the ionized, atomic and molecular phase? These are questions at the heart of cloud and star formation. Methods: Using multiple…

Structural anisotropy in layered two-dimensional materials can lead to highly anisotropic optical absorption which, in turn, can profoundly a^ect their phonon modes. These e^ects include lattice orientation-dependent and excitation…

The effects of Ga+ ion irradiation and high temperature annealing on behavior of nanocrystalline graphene directly grown on quartz and sapphire are presented. It is shown that nanocrystalline graphene stands fairly high doses of ion…

Uniform amorphous carbon film is deposited on the inner surface of quartz tube having the inner diameter of 6 mm and the outer diameter of 8 mm. A pulsed filamentary plasma source is used for the deposition. Long plasma filaments (~ 140 mm)…

Amorphous hydrogenated silicon nitride ($\textit{a}$-SiN$_\mathrm{\textit{x}}$:H) thin films irradiated with 100 MeV Ni$^{7+}$ results in the formation of continuous ion track structures at the lower fluence of $5\times{10^{12}}$…

Based on three years of deep observations of the Galactic center with the Chandra X-ray Observatory, we report the discovery of changes in the intensities and morphologies of two hard X-ray nebulosities. The nebulosities are dominated by…

In this study, a new alternative model algorithm has been proposed for assembling amorphous structures, unifying the bosonic paradigm applicable at low temperatures with crystalline models relevant at room and higher temperatures. Physical…

Controlled defect creation is a prerequisite for the detailed study of disorder effects in materials. Here, we irradiate a graphene/Ir(111)-interface with low-energy Ar+ to study the induced structural changes. Combining computer…

Strain in a material induces shifts in vibrational frequencies, which is a probe of the nature of the vibrations and interatomic potentials, and can be used to map local stress/strain distributions via Raman microscopy. This method is…