RESUMEN
Using a laser-excited angle-resolved photoemission spectroscopy capable of bulk sensitive and high-energy resolution measurements, we reveal a new phenomenon of superconductors in the optimally doped trilayer Bi_{2}Sr_{2}Ca_{2}Cu_{3}O_{10+δ}. We observe a hybridization of the Bogoliubov bands derived from the inner and outer CuO_{2} planes with different magnitudes of energy gaps. Our data clearly exhibit the splitting of coherent peaks and the consequent enhancement of spectral gaps. These features are reproduced by model calculations, which indicate that the gap enhancement extends over a wide range of Fermi surface up to the antinode. The significant modulation of electron pairing uncovered here might be a crucial factor to achieve the highest critical temperature in the trilayer cuprates.
RESUMEN
The modification of the Au(111) Shockley surface state (SS) by an n-alkane molecule (n-tetratetracontane) monolayer was observed by angle-resolved ultraviolet photoemission spectroscopy. Although there is little chance of chemical interaction in this ideal physisorption system, the volume of the Fermi surface of the SS was significantly reduced accompanied by the formation of large interface electric dipoles. Moreover, Rashba splitting of the SS by spin-orbit interactions was slightly increased upon n-tetratetracontane adsorption, which arose from the decrease in the symmetry of the wave function around the Au nuclei at the surface. The detailed information about the simple physisorption system presented in this paper provides basic knowledge for understanding the electronic structure at the interface between other organic molecules and metal substrates.
RESUMEN
We describe a spin- and angle-resolved photoelectron spectroscopy (SARPES) apparatus with a vacuum-ultraviolet (VUV) laser (hν = 6.994 eV) developed at the Laser and Synchrotron Research Center at the Institute for Solid State Physics, The University of Tokyo. The spectrometer consists of a hemispherical photoelectron analyzer equipped with an electron deflector function and twin very-low-energy-electron-diffraction-type spin detectors, which allows us to analyze the spin vector of a photoelectron three-dimensionally with both high energy and angular resolutions. The combination of the high-performance spectrometer and the high-photon-flux VUV laser can achieve an energy resolution of 1.7 meV for SARPES. We demonstrate that the present laser-SARPES machine realizes a quick SARPES on the spin-split band structure of a Bi(111) film even with 7 meV energy and 0.7(∘) angular resolutions along the entrance-slit direction. This laser-SARPES machine is applicable to the investigation of spin-dependent electronic states on an energy scale of a few meV.
RESUMEN
The oral pharmacokinetics of diclofenac (DF) were evaluated in cattle by analyzing plasma concentration-time data after its intravenous and oral administration in order to propose the oral administration of DF as effective route to avoid long withdraw period. DF was intravenously and orally administered at 1 mg/kg to cattle using a crossover design with a 4-week washout period. Plasma concentrations of DF were determined by a HPLC analysis. The mean absorption time (MAT) and absorption half-life (t1/2ka) were 1.61 ± 0.61 and 1.51 ± 0.38 hr, respectively, and bioavailability was nearly 100%. The oral pharmacokinetics of acetaminophen (AAP) were also evaluated in cattle. Plasma concentrations of AAP were determined by a HPLC analysis. MAT and t1/2ka were 2.85 ± 0.93 and 1.53 ± 0.28 hr, respectively, and bioavailability was approximately 70%. In conclusion, the results of the present study indicate that DF and AAP are rapidly absorbed from the forestomach of cattle. Therefore, the appropriate efficacies of these drugs may be achieved via their oral administration, even in cattle.