[en] A simple scheme with the single-particle resonant continuum coupling and pairing correlations, is applied to describe the formation of the giant halo for neutron-rich even-even Zr isotopes by the resonant BCS model within the relativistic mean field framework. Resonance parameters and wave functions are extracted from the effective analytic continuation in the coupling-constant approach. It can be seen that the sudden increase of the neutron radii close to the neutron drip line is due to a few resonant states in the vicinity of the Fermi surface. (orig.)

[en] Low temperature photoluminescence (PL) measurements have been performed for a set of GaN/Al_xGa_1−xN quantum wells (QWs). The experimental results show that the optical full width at half maximum (FWHM) increases relatively rapidly with increasing Al composition in the Al_xGa_1−xN barrier, and increases only slightly with increasing GaN well width. A model considering the interface roughness is used to interpret the experimental results. In the model, the FWHM's broadening caused by the interface roughness is calculated based on the triangle potential well approximation. We find that the calculated results accord with the experimental results well. (condensed matter: electronic structure, electrical, magnetic, and optical properties)