Orbital picture of ionization and its breakdown in nanoarrays of quantum dots

We present exact numerical results indicating that ionization could be a useful tool to study electron correlations in artificial molecules and nanoarrays of metallic quantum dots. For nanorings consisting of Ag quantum dots of the type already fabricated, we demonstrate that the molecular orbital picture breaks down even for lowest energy ionization processes, in contrast to ordinary molecules. Our ionization results yield a transition point between localization and delocalization regimes in good agreement with various experimental data.     

First identification of excited states in 59Zn

Excited states in ⁵⁹Zn were observed for the first time following the fusion-evaporation reaction ²⁴Mg + ⁴⁰Ca at a beam energy of 60 MeV. The GASP array in conjunction with the ISIS Silicon ball and the NeutronRing allowed for the detection of γ-rays in coincidence with evaporated light particles. The mirror symmetry of ⁵⁹Zn and ⁵⁹Cu is discussed. Received: 28 May 2002 / Accepted: 10 July 2002 / Published online: 3 December 2002 RID="a" ID="a"Present address: Oliver Lodge Laboratory, University of Liverpool, P.O. Box 147, Liverpool, L69 7ZE, United Kingdom; e-mail: ca@ns.ph.liv.ac.uk. RID="b" ID="b"Present address: Physik-Departament, Technische Universit?t München, D-85748 Garching, Germany. Communicated by W. Henning     

External Homogenization for Hopf Algebras: Applications to Maschke's Theorem

We apply to Hopf algebras a construction from graded rings, called the group ring of a graded ring. By using this construction we study the transfer of properties between certain categories of relative Hopf modules. As another application, we obtain a Maschke-type theorem for a Galois extension over a semisimple Hopf algebra.     

New approach for numerical solution of configuration-space Faddeev equations

A new computational scheme for solving the bound state configuration-space Faddeev equations is applied. The scheme is based on the spline-approximation and the adiabatic limit of Faddeev equations. An ordering of variables being in agreement with the limit was chosen. As a result the matrix of the eigenvalue problem has a sparse block structure. Calculations of the bound states of µpp, µdd, µtt mesic molecules and ¯pdd, ¯ptt antiprotonic ones, were performed. To check the method, calculations of the binding energies for such systems as the positronium ion Ps_–,³H and³He were carried out. The results are compared with the best results of other authors.     

Electron-microscopy investigations of the damage of aluminium mirrors as a result of repeated powerful microsecond pulsed TEA-CO2 laser irradiation in air

Progressive damage of aluminium mirrors subjected to microsecond pulsed TEA-CO₂ laser irradiation in air, at incident intensity levels lower than the thresholds for melting induction and air breakdown ignition, was evidenced by electron microscopy investigations. A simple model was developed accounting for the results of our experimental studies.     

Crystallization of amorphous metal films within and without magnetic field

Assuming that the conduction electrons of an amorphous metal contribute to the binding, we investigate whether a magnetic field will influence the transition from the amorphous to the crystalline state. Measurements taken on amorphous Bi, Ga and Yb films show no change in the crystallization temperatures within an accuracy of ±0.1 K due to a magnetic field of 18.5 T parallel to the surface of the films.Dedicated to Prof. Dr. W. Buckel on the occasion of his 60th birthday