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991.
Seiichiro Onari Tetsuya Hata Yukio Tanaka Jun-ichiro Inoue 《Journal of Physics and Chemistry of Solids》2008,69(12):3307-3309
In order to clarify the tunneling spectroscopy in high-Tc cuprates, we study electronic state of the surface in the strongly correlated electron systems. First, we obtain Green's function of strongly correlated normal bulk system using the fluctuation exchange (FLEX) approximation. Next, we insert infinite potential into the bulk system and obtain Green's function of surface. We find that the density of states (DOS) in strongly correlated bulk systems are different from that on the surface, and the difference decreases as the magnitude of Coulomb interaction (U) increases. 相似文献
992.
We study the local density of states at the surface of a chiral p-wave superconductor in the presence of a weak magnetic field. As a result, the formation of low-energy Andreev bound states is either suppressed or enhanced by an applied magnetic field, depending on its orientation with respect to the chirality of the p-wave superconductor. Similarly, an Abrikosov vortex, which is situated not too far from the surface, leads to a zero-energy peak of the density of states, if its chirality is the same as that of the superconductor, and to a gap structure for the opposite case. We explain the underlying principle of this effect and propose a chirality sensitive test on unconventional superconductors. 相似文献
993.
Hossain MA Hu Z Haverkort MW Burnus T Chang CF Klein S Denlinger JD Lin HJ Chen CT Mathieu R Kaneko Y Tokura Y Satow S Yoshida Y Takagi H Tanaka A Elfimov IS Sawatzky GA Tjeng LH Damascelli A 《Physical review letters》2008,101(1):016404
Sr3(Ru(1-x)Mnx)2O7, in which 4d-Ru is substituted by the more localized 3d-Mn, is studied by x-ray dichroism and spin-resolved density functional theory. We find that Mn impurities do not exhibit the same 4+ valence of Ru, but act as 3+ acceptors; the extra eg electron occupies the in-plane 3d(x2-y2) orbital instead of the expected out-of-plane 3d(3z2-r2). We propose that the 3d-4d interplay, via the ligand oxygen orbitals, is responsible for this crystal-field level inversion and the material's transition to an antiferromagnetic, possibly orbitally ordered, low-temperature state. 相似文献
994.
Schlappa J Schüssler-Langeheine C Chang CF Ott H Tanaka A Hu Z Haverkort MW Schierle E Weschke E Kaindl G Tjeng LH 《Physical review letters》2008,100(2):026406
Using soft-x-ray diffraction at the site-specific resonances in the Fe L2,3 edge, we find clear evidence for orbital and charge ordering in magnetite below the Verwey transition. The spectra show directly that the (001/2) diffraction peak (in cubic notation) is caused by t2g orbital ordering at octahedral Fe2+ sites and the (001) by a spatial modulation of the t2g occupation. 相似文献
995.
Objective
Fully automatic tissue characterization in intravascular ultrasound systems is still a challenge for the researchers. The present work aims to evaluate the feasibility of using the Higuchi fractal dimension of intravascular ultrasound radio frequency signals as a feature for tissue characterization.Methods
Fractal dimension images are generated based on the radio frequency signals obtained using mechanically rotating 40 MHz intravascular ultrasound catheter (Atlantis SR Plus, Boston Scientific, USA) and compared with the corresponding correlation images.Conclusion
An inverse relation between the fractal dimension images and the correlation images was revealed indicating that the hard or slow moving tissues in the correlation image usually have low fractal dimension and vice-versa. Thus, the present study suggests that fractal dimension images may be used as a feature for intravascular ultrasound tissue characterization and present better resolution then the correlation images. 相似文献996.
Hiroshi Itokawa Nobuaki Yasutake Shintaro Okamoto Ichiro Mizushima 《Applied Surface Science》2008,254(19):6135-6139
Embedded silicon carbon alloy (e-Si:C) technology for source and drain (S/D) is expected to improve nMOSFET drive current. The distribution and activation characteristics of arsenic in Si:C film and the interfacial solid-phase reaction of the Ni/Si:C system were studied with the aim of achieving the maximum improvement of the characteristics of e-Si:C S/D. It was clarified that the active carrier concentration of Si:C decreased with increasing carbon concentration compared to the control Si. There is concern that the low doping activation in Si:C increases series resistance of e-Si:C S/D nMOSFETs and degrades the performance gain expected from the strain effect. 相似文献
997.
T. Tanaka M. Hoshino H. Kato J.R. Harries Y. Tamenori K. Ueda H. Tanaka 《Journal of Electron Spectroscopy and Related Phenomena》2008,164(1-3):24-27
We report soft X-ray total ion yield and angular-resolved ion yield spectra of CF3I in the C 1s, I 3d and F 1s ionisation regions, and tentatively assign the observed electronic states. Anisotropy in ion yield is observed only for the C transition, indicating that the dipole moment for this transition is parallel to the C3v. The effusive source of CF3I is heated to 800 K to produce a mixture of CF3 and I, and the resulting spectra are compared to those recorded at room temperature. 相似文献
998.
We study the fundamental diagram for traffic flow of vehicular mixture on a multi-lane highway. We present the car-following model of multi-lane traffic in which slow and fast vehicles flow with changing lanes. We investigate the traffic states of the vehicular mixture under the periodic boundary. Two values of the current appear at a density and two current curves are obtained. Vehicles move with changing lanes in the traffic state of high current, while vehicles move without changing lanes in the traffic state of low current. They depend on the density, the fraction of slow vehicles, and the initial condition. In the high-current curve, the jamming transition between the free flow and the jammed state occurs at a low density. The fundamental diagrams (current-density diagrams) are shown for the single-lane, two-lane, three-lane, and four-lane traffics. 相似文献
999.
N. Takeyasu T. Tanaka S. Kawata 《Applied Physics A: Materials Science & Processing》2008,90(2):205-209
Three-dimensional silver/polymer conjugated microstructures were fabricated by site-selective metal deposition on photopolymer
structures in the sub-micrometer scale. Photopolymerizable resins with and without an amide group were independently prepared,
and a three-dimensional polymer structure was fabricated with those resins by means of the two-photon-induced photopolymerization
technique to confine the photopolymerization to a sub-micrometer volume. Silver was selectively deposited on the surface of
the amide-containing polymer parts by electroless plating. This method can provide 3D arbitrary silver/polymer composite microstructures
with sub-micrometer resolution.
PACS 81.07-b; 81.16-c; 81.07.Pr 相似文献
1000.