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About 100 fragments of Roman mosaic and millefiori glass were stylistically attributed to a Hellenistic type, a Ptolemaic and Romano-Egyptian period type and an early imperial period type. Twelve representative fragments were studied by electron microprobe analysis and Raman microspectroscopy. Eleven of them display a Napronounced recipe with low K, Mg and P contents, typical for the Roman period. Minor differences in composition are unsystematic, not reflecting the stylistic classification. Ionic colouring agents are Mn 3+ for violet, Cu 2+ for light blue, Co 2+ for deep blue and Fe 3+ for brown translucent colours. Calcium antimonates, lead antimonate and cuprite are the colourants responsible for white, yellow and red colours, respectively, and additionally serve as opacifiers. Mixing of ionic colouring agents and opacifying colourants led to a more differentiated palette of colours. Pb was used as yellow colouring agent, as a flux material and as a stabiliser for the colourant crystals. The remaining fragment consisting of a K-pronounced but still Na-bearing glass matrix was most likely produced during the Middle Ages or later.

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Ancient coloured glass beads from Sri Lanka and Oman were analysed by Raman microspectroscopy for non-destructive identification of inorganic pigments in the glass. Calcium phosphate (Ca 3 (PO 4 ) 2 ), cassiterite (SnO 2 ), cuprite (Cu 2 O) and a Pb(Sn,Si)O 3 -type lead tin oxide were found to be used as colouring agents. Moreover, a distinction between lead-based and alkali-based glass matrices could be made. Electron microprobe analysis and X-ray diffractometry were performed to show the capability of Raman microspectroscopy in comparison to these methods for answering archaeometric questions.

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Superconductor-semiconductor-superconductor junctions with superconducting Nb banks coupled by the degenerate III-V semiconductor n-type InAs are described by the Bogoliubov-de Gennes equations (BdGE) with spatially and energy-dependent effective masses, abruptly changing conduction-band edges, interface barriers, and vanishing pair potential in the semiconducting (Sm) layer. Phase coherence between the superconducting (S) banks is mediated by Andreev scattering of ballistic quasiparticles, which is the only mechanism considered for Cooper pair transfer. The bound-state subbands, broadened by scattering from the mismatches at the S-Sm interfaces, split off at finite phase differences 4 between the pair potentials in either S region. At arbitrary temperatures T below the critical temperature T, of Nb, the Josephson-current density j(4), computed numerically from the solutions of the BdGE, can be simulated very well by j{@)=j, sinl&P Lk;"j{4&)]-, where the kinetic-inductance parameter L";"decreases with increasing temperature and decreasing Sm layer thickness 2a. The maximum coupling energy per unit area is EJ(@=~) = j, h/e for all I k;". The critical Josephson-current density j, is 5.6X10' A cm at T=O K, n =10' cm ', 2a =0.3 pm, and vanishing interface barrier strength Z. j, decreases with increasing 2a, T, and Z; the decrease with temperature becomes more and more pronounced as the electron concentration n in the Sm layer decreases; the decrease with Z can be understood by the Z dependence of the Andreev scattering probability. The Josephson currents computed from Andreev scattering are so large that they should destroy any pair potential possibly induced in the Sm layer by the proximity effect.

The temperature dependence of the energy gap of zinc-blende CdSe and Cd1−xZnxSe has been determined over the entire range of composition from optical transmission and reflection measurements at temperatures between 5 and 300 K. The experimental results can be expressed by the following modified empirical Varshni formula, whose parameters are functions of the composition x: Eg(x,T)=Eg(x,0)−β(x)T2/[T+γ(x)]. Eg(x,0) exhibits a nonlinear dependence on composition, according to Eg=Eg(0,0)(1−x)+Eg(1,0)x−ax(1−x). The parameters β(x) and γ(x) can be expressed by β(x)=β(0)(1−x)+β(1)x+bx(1−x) and γ(x)=γ(0)(1−x)+γ(1)x.

The excavation of the Wattendorf-Motzenstein Corded Ware settlement in Franconia (Germany) has yielded new information with regard to the architecture, economy, and ritual activities, as well as the social organisation of Final Neolithic groups in Central Europe. The settlement is dated to 2660–2470 cal BC and was an agrarian community. Detailed analyses of the material culture combined with biological and pedological parameters allowed new interpretations regarding Corded Ware economies as well as domestic and ritual spheres. The settlement contained about 35 individuals at most, who were organised in fewer than eight households. The exceptional results obtained call for further research strategies to be developed.