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276 Liu, FengThermal roughening of a thin film: a new type of roughening transitionThe equilibrium thermal roughening of thin Ge layers (one and two monolayers) deposited on Si(001) has been investigated with low-energy electron microscopy. A Ge-coverage-dependent roughening is observed. For two monolayers, the temperature at which imaging contrast is lost due to surface roughness...Thermal roughening; Roughening transition; Heteroepitaxial growth2000-09
277 Bedrov, Dmitro; Smith, Grant D.Thermodynamic, transport and viscoelastic properties of PBX-9501 binder: a molecular dynamics simulation studyAtomistic molecular dynamics simulations were performed on a low molecular weight nitroplasticized Estane® mixture representative of the binder used in PBX-9501. Pressurevolume-temperature (PVT) behavior over a wide range of pressure and temperatures above the order-disorder temperature (ODT) of Es...PBX-9501 binder; Estane; Viscosity; Shear stress relaxation modulus2008-04-04
278 Chaudhuri, Reaz A.Three-dimensional singular stress field at the front of a crack and lattice crack deviation (LCD) in a cubic single crystal plateA novel eigenfunction expansion technique, based in part on separation of the thickness variable, is developed to derive three-dimensional asymptotic stress fields in the vicinity of the front of a semi-infinite through-crack weakening an infinite plate made of a homogeneous cubic single crystal. C...2010-05-12
279 Liu, FengTopological and electronic transitions in a Sb(111) nanofilm: the interplay between quantum confinement and surface effectWhen the dimension of a solid structure is reduced, there will be two emerging effects, quantum confinement and surface effect, which dominate at nanoscale. Based on first-principles calculations, we demonstrate that due to an intriguing interplay between these two dominating effects, the topologica...2012-01-01
280 Liu, FengTowards quantitative understanding of formation and stability of Ge hut islands on Si(001)We analyze Ge hut island formation on Si(001), using first-principles calculations of energies, stresses, and their strain dependence of Ge/Si(105) and Ge/Si(001) surfaces combined with continuum modeling. We give a quantitative assessment on strain stabilization of Ge(105) facets, estimate the cr...Ge hut islands; Si(001); First-principles calculations; Heteroepitaxial growth2005-05
281 Chaudhuri, Reaz A.Transverse shear stress distribution through thickness near an internal part-through elliptical hole in a stretched plateA semi-analytical post-processing method, termed the equilibrium/compatibility method here, is used for computation of hitherto unavailable through-thickness variation of transverse shear stresses in the vicinity of the circumferential re-entrant corner line of an internal part-through elliptical ...2010-03
282 Liu, FengTuning nucleation density of metal island with charge doping of graphene substrateWe have demonstrated that the island nucleation in the initial stage of epitaxial thin film growth can be tuned by substrate surface charge doping. This charge effect was investigated using spin density functional theory calculation in Fe-deposition on graphene substrate as an example. It was found ...2014-01-01
283 Liu, FengUnderstanding graphene production by ionic surfactant exfoliation: a molecular dynamics simulation studyWe have simulated sodium dodecyl sulfate (SDS) surfactant/waterþbilayer graphene mixture system to investigate two mechanisms of graphene exfoliation: changing the interlayer distance and sliding away the relative distance. By calculating the total energy as a function of the interlayer (sliding-aw...2014-01-01
284 Liu, FengUnique dynamic appearance of a Ge-Si Ad-dimer on Si(001)We carry out a comparative study of the energetics and dynamics of Si-Si, Ge-Ge, and Ge-Si ad-dimers on top of a dimer row in the Si(001) surface, using first-principles calculations. The dynamic appearance of a Ge-Si dimer is distinctively different from that of a Si-Si or Ge-Ge dimer, providing a ...Ge-Si Ad-dimer; Si(001); First-principles calculations; Energetics2000-12
285 Stringfellow, Gerald B.Use of Nitrogen to disorder GaInPSignificant changes in microstructure, surface structure, and alloy composition have been observed in GaInP with the addition of nitrogen. These effects occur due to surface changes induced by small concentrations of nitrogen. Transmission electron microscopy and photoluminescence experiments indica...Nitrogen; Alloys; Transmission2004
286 Stringfellow, Gerald B.; Shurtleff, James KevinUse of surfactant Sb to induce triple period ordering in GaInPA surfactant is used to induce an ordered structure in an epitaxial layer. The addition of small amounts of triethylantimony during the organometallic vapor phase epitaxy growth of GaInP on 001 GaAs substrates is shown to remove CuPt ordering with a resultant increase in band gap energy. Increasi...Organometallic; Thermodynamics; Surfactant2000-03-13
287 Smith, Grant D.Viscoelastic properties of polybutadiene in the glassy regime from molecular dynamic simulationsA thorough understanding of the dynamic?mechanical properties of polymer melts and glasses is key to many, if not most, applications of polymers as well as to the processing of polymers.Polymer melts; Polymer glasses; Molecular dynamic simulations2002
288 Tiwari, AshutoshZn0.9Co0.1O-based diluted magnetic semiconducting thin filmsHere we report a systematic study of structural, optical, and magnetic measurements on epitaxial Zn0.9Co0.1O films grown on c-plane sapphire single crystal, at various temperatures (500-650°C), using pulsed-laser deposition. The main emphasis in this work has been on the correlation of microstructu...ZnO; Cobalt2004
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