Recent first-principles molecular dynamics simulations (FPMD) results on two chalcogenide glasses (glassy GeS4 and GeSe4) are revisited by accounting explicitly for van der Waals (vdW) dispersion forces. This effort is motivated by the observation that suc ...
Thermal transport is a key feature for the operation of phase change memory devices which rest on a fast and reversible transformation between the crystalline and amorphous phases of chalcogenide alloys upon Joule heating. In this paper we report on the ab ...
Transition metal compounds represent a unique class of solids characterized by a surprising richness of physical properties. They display many phenomena and represent the main area of interest for the research on strongly correlated materials. Many novel i ...
Historically, it is believed that crystalline uraninite, produced via the abiotic reduction of hexavalent uranium (U-(VI)) is the dominant reduced U species formed in low-temperature uranium roll-front ore deposits. Here we show that non-crystalline U-(IV) ...
The amorphous structure of the phase change material Ge2Sb2Te5 (GST) has been the object of controversial structural models. By employing first-principles molecular dynamics within density functional theory, we are able to obtain quantitative agreement wit ...
An average-atom (A-atom) embedded-atom-method potential for random multicomponent alloys at any composition is derived analytically and validated by comparing A-atom and true random alloys bulk and defect properties, in model Fe-Ni-Cr systems. The A-atom c ...
Recently, several research groups have reported the growth of germanene, a new member of the graphene family. Germanene is in many aspects very similar to graphene, but in contrast to the planar graphene lattice, the germanene honeycomb lattice is buckled ...
We investigate the composition and temperature (10-450 K) dependence of the Yb valence in YbMn6Ge6-xSnx (x = 0.0, 3.8, 4.2, 4.4, and 5.5) using resonant inelastic x-ray scattering (RIXS). The observed change in the Yb valence with composition (from v simil ...
Gallium concentration (normalized to CI chondrites) in the mantle is at the same level as that of lithophile elements with similar volatility, implying that there must be little to no gallium in Earth's core. Metal-silicate partitioning experiments, howeve ...
Implementing antireflection (AR) coatings in micromorph tandem solar cells is a challenging process in which not only more sunlight should get conducted into the cells, but also the current matching between subcells should either be maintained or get impro ...
