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Three-dimensionally aligned epitaxial (Pb,La)(Zr,Ti)O3/(La,Sr)2CuO4 multilayers were grown on SrTiO3 (100) single crystals by pulse laser deposition. A cube-on-cube epitaxial relationship of these multilayers was confirmed by the θ-2θ diffraction profile and the pole figure. The stability of their interfaces was confirmed by depth profiles and x-ray diffractometry of the as-deposited and the annealed multilayers having 100–300-Å-thick (La,Sr)2CuO4 layers. The results suggest that the multilayers can be applied to the ferroelectric field-effect transistor.

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We have investigated current-voltage characteristics of individual CdSe colloidal nanodots by conductive-tip atomic force microscopy (AFM). The colloidal nanodots were spun-coat and scattered on a self-assembled monolayer of thiophene molecules formed on Au (111) surfaces for single dot measurements. A thin SiO2 layer was deposited on the sample surface in order to prevent the dots being moved by the tip during measurement. We imaged the topography of isolated single dots by AFM operated in contact mode, and measured current-voltage characteristics with the conductive tip positioned on single dots; large conductivity changes which suggest resonant tunneling through a quantized energy level in the dot was observed even at room temperature.

A single chromophore detection using video-microscopy is one of the latest methodologies to reveal unique characteristics, which could not be obtained from ensemble measurements. Among many kinds of subjects, dynamic optical properties observed in colloidal semiconductor nanoparticles are attractive and important not only for the basis of photo-physics but also for application studies, e.g. biological labeling, electronic devices. In this study, fluorescence video-microscopy was performed on cadmium selenide (CdSe) quantum dots (QDs) spin-coated on a glass substrate. From single CdSe QDs detection, emissions at wavelengths separated over 60 nm were observed for the first time. This spectral feature was attributed to the existence of double-emissive relaxation processes in CdSe QDs. Photoluminescence intermittency was also observed both from relaxation processes. Fluorescence video-microscopy, which was advanced in biology, can be applicable for the real-time monitoring of dynamic properties in semiconductor photo-physics. q

The temperature dependence of the decay of the delayed fluorescence in a naphthalene crystal doped with P-chloronaphthalene is measured. The results are analyzed in terms of the reaction kinetics comprising a term for the collision of a free exciton with an exciton trapped by P-chloronaphthalene (X-trap). The reaction rate constant between the free and trapped excitons is obtained and found to be larger than the reaction rate constants of the triplet exciton with another triplet exciton, a radical, and a guest anthracene molecule in naphthalene crystals. Assuming that the reaction rate constant between the free and trapped excitons is the value at the diffusion limit, the transition probabilities from the neighbouring pair of an exciton and an energy acceptor to the excited state of the energy acceptor are obtained and compared with the results of the analysis using Dexter's theory.Die Temperaturabhiingigkeit des Abklingens der verzogerten Fluoreszenz eines Naphtalinkristalls, der mit P-Chlonutphtalen dotiert wurde, wird gemessen. Die Ergebnisse werden mit Reaktionskinetik analysiert unter EinschluB eines Termes fur den StoB eines freien Exzitons rnit einem durch P-Chlornaphtalen getrapten Exziton (X-Trap). Die Reaktionsrate zwischen den freien und getrapten Exzitonen wirderhalten, und es wirdgefunden, daB sie groler ale dieReaktionsrate eines Triplett-Exzitons mit einem anderen Triplett-Exziton, einem Radikal und einem GastAnthrazenmolekiil in Naphtalinkristallen ist. Unter der Annahme, daB die Reaktionsrate zwischen den freien und getrapten Exzitonen der Wert an der Diffusionsgrenze ist, werden die Ubergangswahrscheinlichkeiten von den Nachbarpaaren eines Exzitons und einem Energieakzeptor zu den ageregten Zustiiinden des Energieakzeptors erhalten und mit Egebnissen einer Analyse mittels der Theorie von Dexter verglichen.