Cheuk‐Wai Tai、S. H. Choy、H.L.W. Chan2008-08-20Journal of the American Ceramic Society
Observations by in situ transmission electron microscopy (TEM) reveal the changes in domains morphology in 0.885(Bi 1/2 Na 1/2 )TiO 3 –0.05(Bi 1/2 K 1/2 )TiO 3 –0.015(Bi 1/2 Li 1/2 )TiO 3 –0.05BaTiO 3 ceramics. Evolution of the macroscopic ferroelectric domains has been observed at 25°–180°C. The ferroelectric domains…
Microwave Dielectric Ceramics SynthesisFerroelectric and Piezoelectric MaterialsMultiferroics and related materials
Zhao Wang、Mariusz Zdrojek、Thierry Mélin 等 4 位作者2008-08-20Physical Review B
We present a detailed study of the static enhancement effects of electric charges in micrometer-long single-walled carbon nanotubes, using theoretically an atomic charge-dipole model and experimentally electrostatic force microscopy. We demonstrate that nanotubes exhibit at their ends surprisingly weak charge enhancem…
Mechanical and Optical ResonatorsCarbon Nanotubes in CompositesForce Microscopy Techniques and Applications
H. Keller、A. Bussmann‐Holder、K. A. Müller2008-08-20Materials Today
The discovery of high-temperature superconductivity in copper oxides was not accidental, but was based on the knowledge that the divalent copper ion, Cu2+, is one of the strongest Jahn–Teller ions. The Jahn–Teller effect is a consequence of the interplay between electronic degeneracy and coupling to the lattice, i.e.…
Superconductivity in MgB2 and AlloysPhysics of Superconductivity and MagnetismIron-based superconductors research
Zhantao Han、Fawang Zhang、Daohui Lin 等 4 位作者2008-08-20Environmental Science & Technology
Carbon nanotubes (CNTs), because of their wide application, will inevitably enter aquatic systems, but the fate and transport of their suspensions in the environment are largely unknown. Clay minerals are expected to interact with CNT suspensions, affecting their fate and bioavailability. This study investigated the i…
Nanoparticles: synthesis and applicationsNanopore and Nanochannel Transport StudiesGraphene and Nanomaterials Applications
Byungkwon Lim、Pedro H. C. Camargo、Younan Xia2008-08-20Langmuir
This article describes a simple approach to anisotropic Au nanostructures with various shapes by reducing HAuCl 4 with poly(vinyl pyrrolidone) (PVP) in aqueous solutions without the use of any additional capping agent or reductant. In this approach, the commercially available PVP servers as a mild reducing agent thank…
Nanomaterials for catalytic reactionsNanocluster Synthesis and ApplicationsGold and Silver Nanoparticles Synthesis and Applications
Javier Carretero‐González、Haris Retsos、Raquel Verdejo 等 7 位作者2008-08-20Macromolecules
The inclusion of highly anisotropic clay nanoparticles (nanoclays) in cross-linked natural rubber (NR) provides a more homogeneous distributed network structure and induces an early onset as well as enhancement of crystallization under uniaxial deformation. The molecular structure of the polymer network and its morpho…
Polymer Nanocomposite Synthesis and IrradiationTribology and Wear AnalysisPolymer Nanocomposites and Properties
Wei Zhou、Hui Wu、Taner Yildirim 等 5 位作者2008-08-20Physical Review B
Metal organic framework-5 (MOF-5) was recently suggested to possess an exceptionally large negative thermal-expansion coefficient. Our direct experimental measurement of the thermal expansion of MOF-5 using neutron powder diffraction, in the temperature range of 4 to 600 K, shows that the linear thermal-expansion coef…
Thermal Expansion and Ionic ConductivityAdvanced Battery Materials and TechnologiesMagnesium Oxide Properties and Applications
H. G. E. Hentschel、Valery Ilyin、Itamar Procaccia2008-08-20arXiv
We present new simulation results for the specific heat in a classical model of a binary mixture glass-former in two dimensions. We show that in addition to the formerly observed specific heat peak there is a second peak at lower temperatures which was not observable in earlier simulations. This is a surprise, as most…
cond-mat.stat-mechMaterials Science
G. L. Ussery、Yu. N. Gartstein2008-08-20arXiv
When an excess charge carrier is added to a one-dimensional (1D) semiconductor immersed in a polar solvent, the carrier can undergo self-localization into a large-radius adiabatic polaron. We explore the local optical absorption from the ground state of 1D polarons using a simplified theoretical model for small-diamet…
Materials Science
Da-Yong Liu、Feng Lu、Liang-Jian Zou2008-08-20arXiv
We develop the cluster self-consistent field method incorporating both electronic and lattice degrees of freedom to study the origin of ferromagnetism in Cs$_{2}$AgF$_{4}$. After self-consistently determining the harmonic and anharmonic Jahn-Teller distortions, we show that the anharmonic distortion stabilizes the sta…
Materials ScienceStrongly Correlated Electrons
A. W. Rushforth、Elisa De Ranieri、Jan Zemen 等 13 位作者2008-08-20Physical Review B
We demonstrate voltage control of the magnetic anisotropy of a (Ga,Mn)As device bonded to a piezoelectric transducer. The application of a uniaxial strain leads to a large reorientation of the magnetic easy axis, which is detected by anisotropic magnetoresistance measurements. Calculations based on the mean-field kine…
Magnetic and transport properties of perovskites and related materialsZnO doping and propertiesMultiferroics and related materials
Gang Zhou、Martin Baumgarten、Kläus Müllen2008-08-20Journal of the American Chemical Society
A series of dimesitylboron (B)- or ditolylamino (N)-substituted ladder-type pentaphenylenes (PP) has been designed and synthesized. The UV-vis absorption spectra of compounds BPPN, BPPB, and NPPN reveal an identical maximum wavelength at 432 nm, which indicates that the B and N centers have very similar contributions…
Molecular Sensors and Ion DetectionLuminescence and Fluorescent MaterialsOrganoboron and organosilicon chemistry
Youngki Yoon、G. Fiori、Seokmin Hong 等 5 位作者2008-08-20IEEE Transactions on Electron Devices
We present an atomistic 3-D simulation study of the performance of graphene-nanoribbon (GNR) Schottky-barrier field-effect transistors (SBFETs) and transistors with doped reservoirs (MOSFETs) by means of the self-consistent solution of the Poisson and Schrodinger equations within the nonequilibrium Green's function (N…
2D Materials and ApplicationsAdvancements in Semiconductor Devices and Circuit DesignGraphene research and applications
Satoshi Koizumi、Christoph Nebel、Milos Nesladek2008-08-20OpenAlex
International audience
Diamond and Carbon-based Materials Research
Peter Stone、Kirstin Alberi、Samuel Tardif 等 7 位作者2008-08-20Physical Review Letters
We have investigated the effect of partial isovalent anion substitution in Ga1-xMnxAs on electrical transport and ferromagnetism. Substitution of only 2.4% of As by P induces a metal-insulator transition at a constant Mn doping of x=0.046 while the replacement of 0.4% As with N results in the crossover from metal to i…
Electronic and Structural Properties of OxidesSemiconductor materials and devicesZnO doping and properties
O. A. Petrenko、G. Balakrishnan、N. R. Wilson 等 6 位作者2008-08-20arXiv
SrEr$_2$O$_4$ has been characterised by low-temperature powder neutron diffraction, as well as single crystal specific heat and magnetisation measurements. Magnetisation measurements show that the magnetic system is highly anisotropic at temperature above ordering. A magnetic field of 280 kOe applied at $T=1.6$ K does…
Strongly Correlated ElectronsMaterials Science
S. H. Curnoe2008-08-20arXiv
It is shown that a k=0, A_{2u} distortion of the terbium tetrahedral network in Tb2Ti2O7 accounts for the apparent isolation of single tetrahedra as seen in neutron scattering studies. Single tetrahedron collective spin states, rather than individual spins, account for the main features of the spin liquid state, namel…
Materials Science
J. H. Jiang、M. W. Wu、Y. Zhou2008-08-20arXiv
Spin kinetics in $n$-type InAs quantum wells under intense terahertz laser fields is investigated by developing fully microscopic kinetic spin Bloch equations via the Floquet-Markov theory and the nonequilibrium Green's function approach, with all the relevant scattering, such as the electron-impurity, electron-phonon…
Materials Science
M. A. Timirgazin、A. K. Arzhnikov2008-08-20arXiv
The spin-spiral (SS) type of magnetization is studied with the Hubbard model. Consideration of noncollinearity of the magnetic moments results in a phase diagram which consists of regions of the SS and paramagnetic states depending on the number of electrons and the parameter U/t (U is the Hubbard repulsion, and t is…
Materials Science
Shuyun Zhou、Donald S. Siegel、А. В. Федоров 等 4 位作者2008-08-20arXiv
The capability to control the type and amount of charge carriers in a material and, in the extreme case, the transition from metal to insulator, is one of the key challenges of modern electronics. By employing angle-resolved photoemission spectroscopy we find that a reversible metal to insulator transition and a fine-…
2D Materials and ApplicationsQuantum and electron transport phenomenaGraphene research and applications