Structure of high spin states of76Kr and78Kr nuclei

Following a fully self-consistent cranked Hartree-Fock-Bogoliubov (CHFB) approach with a pairing+quadrupole+hexadecapole model interaction Hamiltonian the structure of the yrast states of^76,78Kr nuclei is studied up to angular momentumJ = 24. Evolution of the shape with spin, and rotation alignment of proton as well as neutron 0g_9/2 orbitals is investigated along with the inter and intra-nucleus variations of theg factors as a function ofJ. We find that the shape of⁷⁸Kr remains prolate all through up toJ = 24, whereas⁷⁶Kr becomes triaxial beyondJ = 12     

Subgraphs in vertex neighborhoods of Kr‐free graphs

In a K_r‐free graph, the neighborhood of every vertex induces a K_{r ? 1}‐free subgraph. The K_r‐free graphs with the converse property that every induced K_{r ? 1}‐free subgraph is contained in the neighborhood of a vertex are characterized, based on the characterization in the case r ? 3 due to Pach [ 8 ]. © 2004 Wiley Periodicals, Inc. J Graph Theory 47: 29–38, 2004     

运用光电流光谱测定钬原子能级的超精细结构

用自制钬空心阴极灯,运用光电流光谱技术在569nm～600nm谱区内首次测定了元素钬的9条谱线,确定其相应跃迁能级,及超精细结构常数.     

Photovoltaic quantum efficiency enhancement by light harvesting of organo-lanthanide complexes

An increase of about 1% of the delivered power by a mono-crystalline commercial silicon solar cell has been obtained by coating the cell with an active poly-vinylacetate film doped with a light harvesting phenanthroline-Eu³⁺ complex. The dopant absorbs the UV component of the solar spectrum, where the silicon-based cells are almost blind, and emits red light that can be converted with an efficiency close to the maximum. This effect, achieved by a low cost encapsulation process, has been proven for the case of Air Mass 0 lighting conditions, and could be exploited also for terrestrial applications with the proper choice of the organic ligand.     

Polaronic effects in asymmetric quantum wire: An all-coupling variational approach

An all-coupling variational calculation based on Lee-Low-Pines-Huybrechts (LLPH) theory is performed to study the ground state and the first excited state in an asymmetric polar semiconductor quantum wire that is valid for the entire range of the electron-phonon coupling constant and arbitrary confinement length. It is shown that the polaronic effects are very important and size dependent, if the effective width of the wire is reduced below a certain length scale. It is also shown that asymmetry in a quantum wire can be used as an extra parameter to increase the stability of the polaron. Finally the theory is applied to a realistic CdS quantum wire.     

Neutron scattering study of the intermolecular vibrations in solid C60

We present a detailed account of an inelastic neutron scattering study of the intermolecular vibrations in solid C₆₀ above and below the structural phase transformation. Assignment of the observed phonon peaks to modes of translational and librational character is discussed on the basis of lattice dynamical calculations using phenomenological intermolecular potentials. A new bond charge model is presented which reproduces the observed phonon branches very well. However, the apparently small influence of the orientational disorder on the librational excitations remains to be understood.     

Coherent and incoherent phonon processes in artificial atoms

Carrier-phonon interaction in semiconductor quantum dots leads to three classes of phenomena: coherent effects (spectrum reconstruction) due to the nearly-dispersionless LO phonons, incoherent effects (transitions) induced by acoustical phonons and dressing phenomena, related to non-adiabatic, sub-picosecond excitation. Polaron spectra, relaxation times and dressing-related decoherence rates are calculated, in accordance with experiment. Received 30 August 2002 / Received in final form 25 November 2002 Published online 28 January 2003     

电子束泵浦三原子Kr_2F准分子激光的一维动力学研究

应用一维动力学模型，对电子束泵浦Ａｒ／Ｋｒ／Ｆ２混合气体产生的三原子Ｋｒ２Ｆ准分子激光进行了理论模拟研究，指出了提高三原子Ｋｒ２Ｆ准分子激光能量的实验方向，激光能量输出可达毫焦耳量级。     

Susceptibility and electric dipole in metal C 60 compounds

The permanent electric dipole moment of metal atom-C₆₀ compounds is measured. A column (alkali) and a row (transition metals) of the periodic table are systematically investigated. Most of the experimental results are obtained at high temperature when the atom is mobile on the C₆₀ cage. For a given example (NaC₆₀), the dipole moment is also measured by a different method at low temperature and both results are consistent. For alkali, the results are compared to ab initio calculations. A good agreement is obtained, both for absolute values and for the evolution of the bonding in the alkali column. For transition metals, the relative values of the dipole moments are in qualitative agreement with the ionic character of the compounds.