Onset of superfluidity in small CO2(4He)N clusters

We provide definitive theoretical evidence for the onset of superfluidity in small helium clusters doped with molecules at less than one solvation shell, with quantitative analysis of spectroscopic constants for CO2 in (4)He(N) in terms of nonclassical rotational inertia and helium superfluidity calculated by path integral methods. We find a significant superfluid response for N>/=5, with essentially unit response to rotations around the CO2 axis and partial response to rotations about an axis perpendicular to the CO2 axis for N>/=6. This anisotropic superfluid response is shown to be responsible for the N dependence of measured CO2 rotational spectra in (4)He(N).     

Optical properties of singly charged conjugated oligomers: a coupled-cluster equation of motion study

We have implemented a coupled-cluster equation of motion approach combined with the intermediate neglect of differential overlap parametrization and applied it to study the excited states and optical absorptions in positively and negatively charged conjugated oligomers. The method is found to be both reliable and efficient. The theoretical results are in very good agreement with experiments and confirm that there appear two subgap absorption peaks upon polaron formation. Interestingly, the relative intensities of the polaron-induced subgap absorptions can be related to the extent of the lattice geometry relaxations.     

Vibration characteristics of piezoelectric torsional transducers

The vibrational characteristics of Langevin-type torsional transducers, which consist of two piezoelectric torsional disks and two elastic blocks, are studied theoretically and experimentally in this paper. The differential equations of piezoelectric torsional motions are derived in terms of the circumferential displacement and the electric potential. Solutions of the boundary-value problem yield the natural frequencies and mode shapes of the transducers, and the natural frequencies are verified by comparing the numerical results with the experimental ones. The theoretical results enable one to quantitatively predict the effect of the elastic blocks on the reduction of the natural frequencies of a Langevin-type torsional transducer.     

A novel hybrid of Bi-based high-Tc superconductor and molecular complex

Molecular complex HgI2Py2 (Py=pyridine) was intercalated into the Bi-based high-Tc cuprate by intercalative complexation. The intercalation method adopted in this work is based on the new concept, where a neutral ligating agent is diffused into the preintercalated HgI2 layer leading to a charge transfer-type complex formation between the Bi2O2 double layers of Bi2Sr2CaCu2Oy.     

The class number one problem for some non-abelian normal CM-fields of degree 48

We prove that there is precisely one normal CM-field of degree 48 with class number one which has a normal CM-subfield of degree 16: the narrow Hilbert class field of with .

     

Hyperbolic mean growth of bounded holomorphic functions in the ball

We consider the hyperbolic Hardy class , . It consists of holomorphic in the unit complex ball for which and

where denotes the hyperbolic distance of the unit disc. The hyperbolic version of the Littlewood-Paley type -function and the area function are defined in terms of the invariant gradient of , and membership of is expressed by the property of the functions. As an application, we can characterize the boundedness and the compactness of the composition operator , defined by , from the Bloch space into the Hardy space .

     

Baryon rapidity loss in relativistic Au + Au collisions

An excitation function of proton rapidity distributions for different centralities is reported from AGS Experiment E917 for Au+Au collisions at 6, 8, and 10.8 GeV/nucleon. The rapidity distributions from peripheral collisions have a valley at midrapidity which smoothly change to distributions that display a broad peak at midrapidity for central collisions. The mean rapidity loss increases with increasing beam energy, whereas the fraction of protons consistent with isotropic emission from a stationary source at midrapidity decreases with increasing beam energy. The data suggest that the stopping is substantially less than complete at these energies.     

Observability of quantum phase fluctuations in cuprate superconductors

We study the order parameter phase fluctuation effects in cuprate superconductors near T = 0, using a quasi-two-dimensional d-wave BCS model. An effective phason theory is obtained which is used to estimate the strength of the fluctuations, the fluctuation correction to the in-plane penetration depth, and the pair-field susceptibility. We find that, while the phase fluctuation effects are difficult to observe in the renormalization of the superfluid phase stiffness, they may be observed in a pair tunneling experiment which measures the pair-field susceptibility.