By the first-principles electronic structure calculations, we find that the ground state of PbO-type tetragonal alpha-FeTe is in a bicollinear antiferromagnetic order, in which the Fe local moments (approximately 2.5 microB) align ferromagnetically along a diagonal direction and antiferromagnetically along the other diagonal direction on the Fe square lattice. This novel bicollinear order resul...

We have performed a detailed study on the synthesis, the characterization of structural phases and superconductivity of the binary FeSex system from the Fe-rich phase into the Se-rich phase with 0.80≤ x ≤1.20. The results indicate that by long-time lowtemperature annealing, single phase sample could be obtained near the composition of FeSe0.95 with the tetragonal PbO-type structure, while impur...

We study upstream capacity in the network topologies that have been proposed for PBO studies and compare with the upstream capacity that can be obtained when assuming worst-case FEXT. We find that the worst-case FEXT gives a rather tight lower bound for the capacities that are obtained in each of the proposed topologies. Status: For information

Lead-rich intermediate phases, in particular Pt,,Pb and PbO, are found to form on Pt(ll1) atop Ti-buffered Si substrates prior to formation of Pb(Zr, -*TiX)O3 (PZT) thin films. Pt,_,Pb is a [ill] textured transient intermetallic phase that nucleates PZT[111] texture. PbO is a [OOl] textured layer compound that nucleates PZT[100] texture. The formation conditions and lattice matching of these in...

A new lead fluoroborate glass (PbO-PbF2-B2O3) doped with ytterbium (Yb:PbFB) is presented. Samples with different concentrations of Yb3+ were produced and had their emission cross-sections, fluorescence lifetimes and minimum pump intensities determined. They have high refractive index of 2.2 and a density of 4.4 g/cm3. For a doping level of 1.153x1020 ions/cm3, the fluorescence lifetime, after ...