Weihua Wang、K. Pi、Yang Li 等 7 位作者2008-01-08Physical Review B
We report the magnetoresistance (MR) properties of quasi-two-dimensional mesoscopic graphite (MG) spin valve devices consisting of MG flakes contacted by ferromagnetic (FM) electrodes. For devices in which an ultrathin magnesium oxide $(\mathrm{MgO})$ tunnel barrier is inserted at the FM/MG interface, the spin valve e…
Advancements in Battery MaterialsQuantum and electron transport phenomenaGraphene research and applications
Kazunari Matsuda、Tadashi Inoue、Yoichi Murakami 等 5 位作者2008-01-08Physical Review B
We studied the temperature and excitation intensity dependence of exciton luminescence in individual single-walled carbon nanotubes (SWNTs) using single nanotube photoluminescence (PL) spectroscopy. The linear temperature dependence of the PL linewidth in a single SWNT implies that the exciton dephasing is dominated b…
Carbon Nanotubes in CompositesFullerene Chemistry and ApplicationsMechanical and Optical Resonators
Weili Qiang、Yilong Wang、Ping He 等 6 位作者2008-01-08Langmuir
Asymmetric nanocomposite particle pairs of polystyrene and silica were prepared via one-step miniemulsion polymerization for the first time. The transmission electron microscopy images showed that these nanocomposite particle pairs were monodisperse and highly asymmetric in morphology. The key to obtaining the asymmet…
Pickering emulsions and particle stabilizationSurfactants and Colloidal SystemsAdvanced Polymer Synthesis and Characterization
Sucismita Chutia、S. N. Coppersmith、Mark Friesen2008-01-08arXiv
The coupling between $z$ valleys in the conduction band of a Si quantum well arises from phenomena occurring within several atoms from the interface, thus ruling out a theoretical description based on pure effective mass theory. However, the complexity and size of a realistic device precludes an analytical atomistic d…
Materials ScienceMesoscale and Nanoscale Physics
Mehmet Kahraman、M. Müge Yazıcı、Fikrettin Şahi̇n 等 4 位作者2008-01-08Langmuir
A sample preparation method based on convective assembly for "whole-microorganism" identification using surface-enhanced Raman scattering (SERS) is developed. With this technique, a uniform sample can easily be prepared with silver nanoparticles. During the deposition process, bacteria and nanoparticles are assembled…
Spectroscopy Techniques in Biomedical and Chemical ResearchGold and Silver Nanoparticles Synthesis and ApplicationsBiosensors and Analytical Detection
S. D. Yoon、C. Vittoria、V. G. Harris 等 6 位作者2008-01-08arXiv
Nano granular metallic iron (Fe) and titanium dioxide (TiO$_{2-δ}$) were co-deposited on (100) lanthanum aluminate (LaAlO$_3$) substrates in a low oxygen chamber pressure using a pulsed laser ablation deposition (PLD) technique. The co-deposition of Fe and TiO$_2$ resulted in $\approx$ 10 nm metallic Fe spherical grai…
cond-mat.otherMaterials Science
Y. Jiao、F. H. Stillinger、S. Torquato2008-01-08arXiv
In the first part of this series of two papers, we proposed a theoretical formalism that enables one to model and categorize heterogeneous materials (media) via two-point correlation functions S2 and introduced an efficient heterogeneous-medium (re)construction algorithm called the "lattice-point" algorithm. Here we d…
Materials Science
B. G. Park、J. Wunderlich、D. A. Williams 等 9 位作者2008-01-08arXiv
We report observations of tunneling anisotropic magnetoresitance (TAMR) in vertical tunnel devices with a ferromagnetic multilayer-(Co/Pt) electrode and a non-magnetic Pt counter-electrode separated by an AlOx barrier. In stacks with the ferromagnetic electrode terminated by a Co film the TAMR magnitude saturates at 0…
Materials Science
Alexander B. Shick、Alexander I. Lichtenstein2008-01-08arXiv
The orbital magnetic moment of a Co adatom on a Pt(111) surface is calculated in good agreement with experimental data making use of the LSDA+U method. It is shown that both electron correlation induced orbital polarization and structural relaxation play essential roles in orbital moment formation. The microscopic ori…
Strongly Correlated ElectronsMaterials Science
Sebastian Panknin、Alexander K. Hartmann、Tim Salditt2008-01-08arXiv
We use the parabolic wave equation to study the propagation of x-rays in tapered waveguides by numercial simulation and optimization. The goal of the study is to elucidate how beam concentration can be best achieved in x-ray optical nanostructures. Such optimized waveguides can e.g. be used to investigate single biomo…
Materials Science
John Kitchin、Karsten Reuter、Matthias Scheffler2008-01-08arXiv
We present a first-principles atomistic thermodynamics framework to describe the structure, composition and segregation profile of an alloy surface in contact with a (reactive) environment. The method is illustrated with the application to a Ag3Pd(111) surface in an oxygen atmosphere, and we analyze trends in segregat…
Materials Science
Panaghiotis Karamanis、Claude Pouchan、George Maroulis2008-01-08Physical Review A
We have employed conventional ab initio and density-functional-theory (DFT) methods to study the structure, stability and electric polarizability of small gallium arsenide clusters ${\mathrm{Ga}}_{n}{\mathrm{As}}_{n}$. We relied on purpose-oriented, carefully optimized basis sets of Gaussian-type functions. We have ca…
Quantum Dots Synthesis And PropertiesElectronic and Structural Properties of Oxides2D Materials and Applications
Michal Soreni‐Harari、Nir Yaacobi‐Gross、D. Steiner 等 7 位作者2008-01-08Nano Letters
We demonstrate tuning of the electronic level positions with respect to the vacuum level in colloidal InAs nanocrystals using surface ligand exchange. Electrochemical as well as scanning tunneling spectroscopy measurements reveal that the tuning is largely dependent on the nanocrystal size and the surface linking grou…
Electronic and Structural Properties of OxidesQuantum Dots Synthesis And PropertiesChalcogenide Semiconductor Thin Films
A. Gliesche、C. Michel、V. Rajevac 等 7 位作者2008-01-08arXiv
The effect of exchange interactions within spin pairs on spin-dependent transport and recombination rates through localized states in semiconductors during coherent electron spin resonant excitation is studied theoretically. It is shown that for identical spin systems, significant quantitative differences are to be ex…
Materials Science
N. Rougemaille、M. Portalupi、A. Brambilla 等 8 位作者2008-01-08arXiv
Using spin-polarized low-energy electron microscopy to study magnetization in epitaxial layered systems, we found that the area vs perimeter relationship of magnetic domains in the top Fe layers of Fe/NiO/Fe(100) structures follows a power-law distribution, with very small magnetic domain cutoff radius (about 40 nm) a…
Materials Science
Troels Markussen、Riccardo Rurali、Antti-Pekka Jauho 等 4 位作者2008-01-08arXiv
We consider the electronic transport properties of phosphorus (P) doped silicon nanowires (SiNWs). By combining ab initio density functional theory (DFT) calculations with a recursive Green's function method, we calculate the conductance distribution of up to 200 nm long SiNWs with different distributions of P dopant…
Mesoscale and Nanoscale PhysicsMaterials Science
C. Ataca、S. Cahangirov、E. Durgun 等 5 位作者2008-01-08arXiv
In this paper we investigated structural, electronic and magnetic properties of 3d (light) transition metal (TM) atomic chains using first-principles pseudopotential plane wave calculations. Periodic linear, dimerized linear and planar zigzag chain structures and their short segments consisting of finite number of ato…
Materials Science
Rahul Tripathi、V. P. S. Awana、H. Kishan 等 5 位作者2008-01-08arXiv
La0.7Ba0.3MnO3 (LBMO):Agx (x = 0.0, 0.1, 0.2, 0.3, and 0.4) composites are synthesized by solid-state reaction route, the final sintering temperatures are varied from 1300 (LBMO1300Ag) to 1400 0C (LBMO1400Ag), and their physical properties are compared as a function of temperature and Ag content. All samples are cryst…
Strongly Correlated ElectronsMaterials Science
Aurore Schneider、Jonathan A. Garlick、Christophe Egles2008-01-08PLoS ONE
Cutaneous wound repair regenerates skin integrity, but a chronic failure to heal results in compromised tissue function and increased morbidity. To address this, we have used an integrated approach, using nanobiotechnology to augment the rate of wound reepithelialization by combining self-assembling peptide (SAP) nano…
Polydiacetylene-based materials and applicationsAntimicrobial Peptides and ActivitiesSupramolecular Self-Assembly in Materials
Matthew Menke、Bonnie Berger、Lenore Cowen2008-01-08PLoS Computational Biology
Even when there is agreement on what measure a protein multiple structure alignment should be optimizing, finding the optimal alignment is computationally prohibitive. One approach used by many previous methods is aligned fragment pair chaining, where short structural fragments from all the proteins are aligned agains…
Enzyme Structure and FunctionGenomics and Phylogenetic StudiesProtein Structure and Dynamics