NASA Scientific and Technical Aerospace Reports

20060001932 Air Force Research Lab., Kirkland AFB, NM USA
Size-Dependence of the Linear and Nonlinear Optical Properties of GaN nanoclusters
Pineda, Andrew C.; Karna, Shashi P.; Jan. 1, 2005; 10 pp.; In English; Original contains color illustrations
Contract(s)/Grant(s): Proj-2305
Report No.(s): AD-A440626; No Copyright; Avail.: CASI: A02, Hardcopy
In this paper, we present the results of our first-principles quantum mechanical studies of the electronic structure,
geometry, and linear and nonlinear optical (NLO) properties of tetrahedral GaN atomic clusters. Our calculated results suggest
that the linear and NLO properties both exhibit a strong dependence upon cluster size and shape (geometry). However, the
size- and the geometry-dependences are more pronounced for the NLO properties than for the linear optical properties. For
clusters containing equal numbers of Ga and N atoms, an open-structure with no network-forming ring has a much larger
second-order NLO coefficient than a cluster with a closed ring structure.
DTIC
Gallium Nitrides; Linear Systems; Nanotechnology; Nonlinear Systems; Nonlinearity; Optical Properties
20060001933 Jiaotong Univ., Shanghai, China
New Graduate Student for Silicon QC Project
Tucker, John R.; Oct. 8, 2005; 6 pp.; In English
Contract(s)/Grant(s): DAAD19-01-1-0579
Report No.(s): AD-A440645; ARO-42643.1-PH-QC; No Copyright; Avail.: CASI: A02, Hardcopy
This grant has provided funding for an additional graduate student, Stephen J. Robinson, to work on ARO/ARDA project
DAAD-19-00-1-0407, ‘Controlled Coupling of Donor Atom Wavefunctions in Silicon’, at the University of Illinois under the
supervision of Co-PI John Tucker. Stephen’s research involves fabrication of the ion-implanted contact arrays used for
atom-scale STM P donor device fabrication, and low temperature measurements to characterize their properties. His efforts
have been closely coordinated with T.-C. Shen, PI, and my fifth-year graduate student Jeffrey Kline working at Utah State
University. Dr. Kline has recently graduated with a Ph.D. and is currently a NIST Fellow at Boulder, working to fabricate
epitaxial superconductor tunnel junctions for QC experiments in that area. A portion of his salary as a graduate student was
also supported by this grant. Stephen Robinson has recently moved to Utah State and will complete his Ph.D. in the coming
year. He and Prof. Shen are currently working to demonstrate epitaxial single-electron transistors for use in QC spin-state
detection. Both Stephen and Jeff have made very substantial contributions to demonstrating P-donor nanowires as the first step
toward an integrated Si QC architecture.
DTIC
Quantum Theory; Silicon; Students
20060002341 ISRO Satellite Centre, Peenya, Bangalore, India
Understanding Pseudo Electrolyte-Leak Behaviour in Ni/H2 Cells
Veena, R.; Venugopalan, S.; Usha, K.; Journal of Spacecraft Technology, Volume 15, No. 2; July 2005, pp. 40-45; In English;
See also 20060002338; Copyright; Avail.: Other Sources
This paper presents experiments conducted to prove that even a potential difference of the order of 0.3 V to 1 V that
typically exists between cell terminal and cell case of positively precharged Ni-H2 cells, in fully discharged open circuit
conditions may cause pseudo indication of electrolyte leak in the cells.
Author
Electrolytes; Hydrogen; Leakage
20060002363 Lawrence Livermore National Lab., Livermore, CA USA
DPB Hydrogen Getters on Pd (110) Its Action and the Effect of Impurities
Maiti, A.; Gee, R.; Mar. 14, 2005; 12 pp.; In English
Report No.(s): DE2005-15016405; UCRL-CONF-210504; No Copyright; Avail.: Department of Energy Information Bridge
Density Functional Theory (DFT) is used to investigate the action of hydrogen getter 1,4-diphenyl-butadiyne, or DPB,
on Pd(110) surface. We study reaction pathways and energetics of several relevant processes, including H(sub 2) adsorption,
dissociation and migration on the metal surface, getter-metal interaction, and the energetics of H uptake by the getter. We also
explore the effect of impurities like CO and CO(sub 2) on the action of the getter. Activation barriers for certain reactions are
37