Universal heat transport in Sr2RuO4

We present the temperature dependence of the thermal conductivity kappa(T) of the unconventional superconductor Sr2RuO4 down to low temperatures ( approximately 100 mK). In the T-->0 K limit we found a finite residual term in kappa/T, providing clear evidence for the superconducting state with an unconventional pairing. The residual term remains unchanged for samples with different T(c), demonstrating the universal character of heat transport in this spin-triplet superconductor. The low-temperature behavior of kappa suggests the strong impurity scattering with a phase shift close to pi/2. A criterion for the observation of universality is experimentally deduced.     

Tuning of spin density wave strengths in quasi-one-dimensional mixed-halogen-bridged nickel(III) complexes with strong electron correlation, [Ni(III)(chxn)(2)Cl(1-x)Br(x)](NO(3))(2)

This communication describes the syntheses of the quasi-one-dimensional mixed-halogen-bridged Ni(III) complexes with strong electron correlation [Ni(chxn)(2)Cl(1-x)Br(x)](NO(3))(2) and the tuning of the spin density wave strengths of these compounds. If the Cl 3p and Br 4p make one band in the compounds, we should observe a single peak in the electronic spectra. As a result, we should observe the single peak from 1.45 to 2.00 eV depending on the mixing ratios of Cl and Br ions. Therefore, the Cl 3p and Br 4p make one band. Then, we have succeeded in tuning the spin density wave strengths of the Ni(III) complexes with the strong electron correlation by mixing the bridging halogen ions successively.     

A bayesian approach to the probability density estimation

Summary A Bayesian procedure for the probability density estimation is proposed. The procedure is based on the multinomial logit transformations of the parameters of a finely segmented histogram model. The smoothness of the estimated density is guaranteed by the introduction of a prior distribution of the parameters. The estimates of the parameters are defined as the mode of the posterior distribution. The prior distribution has several adjustable parameters (hyper-parameters), whose values are chosen so that ABIC (Akaike's Bayesian Information Criterion) is minimized. The basic procedure is developed under the assumption that the density is defined on a bounded interval. The handling of the general case where the support of the density function is not necessarily bounded is also discussed. The practical usefulness of the procedure is demonstrated by numerical examples. The Institute of Statistical Mathematics     

Emission of thermal energy into liquid helium

Thermal energy of a pulse heated Ni film on a Si substrate is depleted with high efficiency under contract with liquid He. The depletion rate was studied by means of longitudinal and transverse phonon pulses released into the substrate.     

Formation and reactions of aryldiazomethane radical cations

Dicyanoanthracene-sensitized photolysis of aryldiazomethanes affords stilbenes with cis/trans ratios of ～3 via free radical cations; anodic oxidation gives similar results but via radical cations adsorbed on electrode surface.     

Quenching effect of the anion ordering in the organic superconductor (TMTSF)2ClO4: An X-ray study

In the title compound it is found directly by an X-ray diffuse scattering study that the orientational ordering of ClO₄ anions is suppressed when a sample is quenched from higher temperature to 15K. Also the lattice parameter is found to be frozen on quenching. Possible interrelation between these phenomena and the onset of superconductivity is discussed briefly.     

Vibrational structures of a few electronic bands of thioformamide

Vibrational structures of four electronic bands of thioformamide were examined: Three were observed at 8.70, 9.30, and 15.52 eV in the photoelectron spectrum, and one was observed at 230 nm in the absorption spectrum. The four corresponding bands of thioformamide-d₂ have also been examined. On the Condon approximation, and on the assumption that the vibrations are all harmonic, the amount of shift in the potential minimum along each normal coordinate, which is caused by each electronic transition (ionization or excitation), has been estimated.