0000000000447147
AUTHOR
O. Lang
Thin film growth and band lineup of In2O3 on the layered semiconductor InSe
Thin films of the transparent conducting oxide In2O3 have been prepared in ultrahigh vacuum by reactive evaporation of indium. X-ray diffraction, optical, and electrical measurements were used to characterize properties of films deposited on transparent insulating mica substrates under variation of the oxygen pressure. Photoelectron spectroscopy was used to investigate in situ the interface formation between In2O3 and the layered semiconductor InSe. For thick In2O3 films a work function of φ = 4.3 eV and a surface Fermi level position of EF−EV = 3.0 eV is determined, giving an ionization potential IP = 7.3 eV and an electron affinity χ = 3.7 eV. The interface exhibits a type I band alignmen…
Optical and photovoltaic properties of indium selenide thin films prepared by van der Waals epitaxy
Indium selenide thin films have been grown on p-type gallium selenide single crystal substrates by van der Waals epitaxy. The use of two crucibles in the growth process has resulted in indium selenide films with physical properties closer to these of bulk indium selenide than those prepared by other techniques. The optical properties of the films have been studied by electroabsorption measurements. The band gap and its temperature dependence are very close to those of indium selenide single crystals. The width of the fundamental transition, even if larger than that of the pure single crystal material, decreases monotonously with temperature. Exciton peaks are not observed even at low temper…
ChemInform Abstract: Magnetic and Electronic Structure of the CMR Chalcospinel Fe0.5Cu0.5Cr2S4
Magnetic and structural properties of the double-perovskite Ca2FeReO6
Abstract We suceeded in the preparation of polycrystalline Ca2FeReO6 which has a Curie temperature TC of 540 K, the highest value of all magnetic perovskites investigated till now. This material has been characterised by X-ray and neutron powder diffraction. We found at 548 K, a monoclinic unit cell (space group P21/n) with a=5.4366(5) A , b=5.5393(5) A , c=7.7344(5) A , and β=90.044(4)°. For temperatures below 400 K, a phase separation in two monoclinic phases with identical cell volume is observed in neutron scattering. The two phases possess different magnetic structure and coercivity. The conductivity is thermally activated for all temperatures and no significant magnetoresistivity is o…
Modulated Crystal Structure and Electronic Properties of Semiconductor Cu47Si91P144
Crystals of the copper silicon phosphide were synthesized by the iodine gas transport technique. The x-ray single crystal methods revealed a big superstructure with the lattice parameters a = b = 44.510 and c = 20.772 A and a basic tetragonal substructure with a = 3.7092 and c = 5.1930 A. Analysis of the intensities showed that the superstructure has a 1/2,1/2,1/2 tetragonal substructure with a = 22.255 and c = 10.386 A. This 1/2,1/2,1/2 substructure (Cu47Si91P144) and the basic tetragonal structure (Cu0.71Si1.29P2) were solved by the direct methods and refined in the I4m2 space group. The phosphide is a semiconductor with a small energy gap of 0.0269(1) eV. The electrical properties are co…