We make glass of dilute LiCl aqueous solution by cooling micrometer-sized droplets of the solution extremely quickly and measure the Raman spectra of the glass. It is found that the OH stretching vibration mode of the...
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We make glass of dilute LiCl aqueous solution by cooling micrometer-sized droplets of the solution extremely quickly and measure the Raman spectra of the glass. It is found that the OH stretching vibration mode of the glass of dilute solution is composed of the OH stretching vibration mode of pure glassy water and that of the glass of solvent water in the highly concentrated solution. This is consistent with the possibility of the existence of two distinct glassy states of water in dilute LiCL solution at low temperature.
According to the liquid-liquid critical-point hypothesis about water, two liquid waters exist at low temperatures and are supposed to be merged at a critical point. The low-temperature metastable melting curves of D2O...
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According to the liquid-liquid critical-point hypothesis about water, two liquid waters exist at low temperatures and are supposed to be merged at a critical point. The low-temperature metastable melting curves of D2O ices have been measured. It is found that the melting curve of D2O ice III is smoothly curved around 25 MPa and 238 K, whereas the melting curve of D2O ice IV undergoes an abrupt change of slope at 100 MPa and 220 K. This is consistent with the existence of a liquid-liquid critical point in the region between the melting curve of D2O ice III and the melting curve of D2O ice IV.
Phase transitions in solid DCl have been investigated by Raman spectral measurement up to 70 GPa at 298 K. The I-III phase transition accompanied by orientational ordering of the molecules took place at 19.0±0.5G...
Phase transitions in solid DCl have been investigated by Raman spectral measurement up to 70 GPa at 298 K. The I-III phase transition accompanied by orientational ordering of the molecules took place at 19.0±0.5GPa, exactly the same pressure as observed for solid HCl. A further transition with hydrogen bond symmetrization (III-IV transition) was observed at about 56±2GPa higher by 5 GPa than the symmetrization pressure of HCl previously determined. The bond symmetrization is realized when the midpoint barrier separating two potential minima along the hydrogen-bonding axis is depressed and smeared out quantum mechanically. The observed isotope effects on the symmetrization pressure are hence interpreted in terms of proton (deuteron) tunneling transfer in the hydrogen bonding potential, which gradually is deformed toward a single minimum shape with increasing pressures.
We report Cu-NMR studies of the multilayered high-Tc cuprate (Cu0.6C0.4)Ba2Ca3Cu4O12+y (Cu1234) with Tc=117 K. In the normal state, the Knight shift (K) and the nuclear spin-lattice relaxation rate (1/T1) of 63Cu give...
We report Cu-NMR studies of the multilayered high-Tc cuprate (Cu0.6C0.4)Ba2Ca3Cu4O12+y (Cu1234) with Tc=117 K. In the normal state, the Knight shift (K) and the nuclear spin-lattice relaxation rate (1/T1) of 63Cu give evidence that the inner CuO2 planes (IP) are underdoped, whereas the outer ones (OP) are heavily overdoped. In the superconducting (SC) state, both K and 1/T1 decrease markedly below Tc=117 K in the IP, whereas in the OP they decrease moderately below Tc=117 K, but markedly below Tc2=60 K. The unusual NMR results in the OP reveal that the SC gap does not fully develop down to Tc2=60 K. From comparison with a conventional d-wave model, it is shown that the SC gap in the OP increases linearly below Tc and follows the mean-field type of T dependence below Tc2. We propose that these dissimilarities are caused by the large difference of doping levels between the IP and the OP. The bulk SC transition at Tc=117 K is considered to be triggered by the underdoped IP in Cu1234.
Direct experimental estimations of the low-energy (1.5–10 meV) complex dielectric constants spectrum and its temperature variation have been investigated for La0.7Ca0.3MnO3 thin films using terahertz time-domain spec...
Direct experimental estimations of the low-energy (1.5–10 meV) complex dielectric constants spectrum and its temperature variation have been investigated for La0.7Ca0.3MnO3 thin films using terahertz time-domain spectroscopy. At low temperatures, a clear Drude term emerges. With increasing temperature, the scattering rate increases, while the plasma frequency decreases, both derived from a simple Drude model. Finally, a Drude term submerges well below the insulator-metal transition temperature. On the basis of the present results, low-energy charge dynamics are discussed.
We investigated the behavior of the spin-triplet superconductor Sr2RuO4 ( Tc≈1.5K) under the magnetic fields parallel to the quasi-two-dimensional plane. The upper critical field Hc2 exhibits a clear fourfold anisotr...
We investigated the behavior of the spin-triplet superconductor Sr2RuO4 ( Tc≈1.5K) under the magnetic fields parallel to the quasi-two-dimensional plane. The upper critical field Hc2 exhibits a clear fourfold anisotropy of about 3% at 0.35 K. Furthermore, we detected an additional transition feature below Hc2 in both the ac susceptibility and the specific heat. These second-transition features as well as the pronounced in-plane Hc2 anisotropy disappear above 0.8 K or under intentional field misalignment of less than 1°. Most of these characteristics are consistent with the predicted emergence of the second superconducting phase with a line-node gap.
We performed propagation experiments of 150-fs optical pulses at the exciton resonance in CuCl. We observed several types of optical precursors corresponding to the Sommerfeld, the Brillouin, and the exciton precursors.
ISBN:
(纸本)1557526451
We performed propagation experiments of 150-fs optical pulses at the exciton resonance in CuCl. We observed several types of optical precursors corresponding to the Sommerfeld, the Brillouin, and the exciton precursors.
Using a two-dimensional spatial light amplitude and phase-modulator, simultaneous multicolor pulse shaping of coherent ultrabroadband (600 to 850 nm) optical pulses generated by self-phase modulation in an Ar-gas fill...
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ISBN:
(纸本)1557526451
Using a two-dimensional spatial light amplitude and phase-modulator, simultaneous multicolor pulse shaping of coherent ultrabroadband (600 to 850 nm) optical pulses generated by self-phase modulation in an Ar-gas filled fiber, being applicable for multicolor coherent wave-packet control, was demonstrated.
A nonlinear time series prediction scheme is proposed with a combination of model dynamical systems weighted by model marginal likelihoods. The scheme outperforms prediction with a single model prediction with the hig...
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A nonlinear time series prediction scheme is proposed with a combination of model dynamical systems weighted by model marginal likelihoods. The scheme outperforms prediction with a single model prediction with the highest marginal likelihood.
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