Pr(1--x)CaxMnO(3) and Nd(1--x)SrxMnO(3) were investigated with three-photon difference frequency generation (DFG). This method allows one to determine both the crystalline and the magnetic symmetry. ...In the highly ordered low-temperature phase of Nd(0.50)Sr(0.50)MnO(3), a DFG contribution coupling simultaneously to antiferromagnetic and charge ordering was observed and used to reveal the formation of domains. Thus, magnetically induced three-photon processes are introduced into the fields of both nonlinear magneto-optics and colossal magnetoresistance as a powerful new method.
A model is proposed that describes the essential optical process in the recently observed resonant light scattering from a microsphere resonator that is strongly coupled to the substrate. The ...experimentally observed field patterns across the resonance can be reproduced quite well by a numerical calculation taking into account only a few vector spherical waves that are converted from nonpropagating to propagating waves at the substrate surface. Explicit consideration of the multiple-reflection effect is not necessary to reproduce the experimental results. Comparison of the experiment and the calculation suggests the splitting of degenerate resonance modes that have different azimuthal mode numbers within a single broad resonance line. These results are discussed on the basis of the strongly coupled nature of the system.
Transition-metal compounds with spin, charge, and orbital degrees of freedom tend to have frustrated electronic states coupled with local lattice distortions and to show drastic response to external ...stimuli such as photo-excitation. We have studied the charge-orbital states in perovskite-type Pr0.55(Ca1-ySry)0.45MnO3 thin films (PCSMO) and spinel-type CuIr2S4 using photoemission spectroscopy combined with additional laser illumination. PCSMO and CuIr2S4 are clear-cut examples of transition-metal compounds showing photo-induced metallic conductivities but the charge-orbital states in the two systems show contrasting responses to the photo-excitation. The charge-orbital states in PCSMO are stabilized by Jahn-Teller or Breathing-type lattice distortions and can be destroyed by photo-excitation. On the other hand, the charge-orbital states in CuIr2S4 are stabilized by dimer formation and tend to be robust against photo-excitation.
The light-induced insulator-metal transition in the "colossal magnetoresistance" compound Pr0.7Ca0.3MnO3 is shown in a study to generate a well-localized conducting path while the bulk of the sample ...remains insulating.
The dissolution behavior of α-SiC coated with amorphous SiO
2 films 0.67 ± 0.34 nm thick and the adsorption of Al ions onto SiC surface were studied in 1.0 vol.% solid suspensions containing 0.37 or ...3.7 mM of Al(NO
3)
3 at pH 3–10. In the suspension at pH 3–7, the SiO
2 films and H
2O interacted to form soluble H
4SiO
4. The amount of SiO
2 dissolved in the SiC suspensions was dominated by the solubility limit of surface SiO
2 films and increased at pH 10 due to the formation of H
3SiO
4
− and H
2SiO
4
−2 ions. The addition of Al(NO
3)
3 to the neutral and basic suspensions suppressed the dissolution of the SiO
2 films. The neutral SiC surface near the isoelectric point (pH 3.1) adsorbed no Al
3+ ions or just a trace. The negatively charged SiC surface adsorbed 1.13 μmol of Al
3+ ions m
−2 at pH 4. In the pH range 5–8, negatively charged SiC particles coexisted with positively charged Al(OH)
3 precipitate was charged negatively at pH 10 because its isoelectric point was pH 9.0 and some Al(OH)
3 dissolved as Al(OH)
4
− ions.
Tramadol has been used as an analgesic for several decades. µ-Opioid receptors (µORs) are the major receptors that mediate the analgesic effects of opioids. Although µORs have been thought to be one ...of the sites of action of tramadol, there has been no report that directly proves whether tramadol is an agonist of μOR or not. In this study, we examined the effects of tramadol and its main active metabolite
O
-desmethyltramadol (M1), on the function of µORs using
Xenopus
oocytes expressing cloned human µORs. The effects of tramadol and M1 were evaluated using the Ca
2+
-activated Cl
−
current assay method for G
i/o
-protein-coupled receptors by using a µOR fused to G
qi5
(µOR-G
qi5
) in
Xenopus
oocytes. DAMGO (
d
-Ala
2
,
N
-MePhe
4
, Gly
5
-ol)-enkephalin evoked Cl
−
currents in oocytes expressing µOR-G
qi5
in a concentration-dependent manner. Tramadol and M1 also evoked Cl
−
currents in the oocytes expressing µOR-G
qi5
; however, relatively higher concentrations (compared to DMAGO) were necessary to induce such currents. Tramadol and M1 had a direct effect on µORs expressed in
Xenopus
oocytes. Although the monoamine uptake system and several types of ligand-gated ion channels are thought to be one of the targets for tramadol, tramadol-induced antinociception may be mediated at least in part, by the direct activation of µORs.
A data sample of 1040 days from the Kamiokande II detector, consisting of subsamples of 450 days at electron-energy threshold E(e) greater than or equal to MeV and 590 days at E(e) greater than or ...equal to 7.5 MeV, yields a clear directional correlation of the solar-neutrino-induced electron events with respect to the sun and a measurement of the differential electron-energy distribution. These provide unequivocal evidence for the production of B-8 by fusion in the sun. The measured flux of B-8 solar neutrinos from the two subsamples relative to a prediction of the standard solar model is 0.46 + or - 0.05 (stat) + or - 0.06 (syst). The total data sample is tested for short term time variation and, within the statistical error no significant variation is observed. (Author)
Robustness of a selective epitaxial growth of silicon is demonstrated. The process window of selectivity was estimated quantitatively using the Taguchi method and signal-to-noise ratio analysis for ...the first time. Both the number of the silicon nuclei on the mask layer and the growth rate of silicon on a silicon substrate were investigated as the output parameters of the Taguchi method. One of the most effective process parameters for the suppression of silicon nucleation on the mask layer without retarding the growth rate of silicon is revealed to be the flow rate of SiH/sub 2/Cl/sub 2/. By calculating the number of the silicon nuclei, which could not be detected by an available measurement method, the process window of the selectivity could be determined with which a wafer with selective epitaxial silicon layer having LSI-quality could be fabricated. A high-quality silicon-on-insulator (SOI) wafer that has both an SOI region and bulk-silicon region can be obtained, and a high-quality embedded device could be realized on the SOI wafer.
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