Sophia University

About: Sophia University is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Nonlinear system & Catalysis. The organization has 4986 authors who have published 7657 publications receiving 106567 citations. The organization is also known as: Jōchi Daigaku.

Sympathetic crystallization of CaH + produced by a laser-induced reaction

Abstract: We investigated sympathetic Coulomb crystallization of CaH${}^{+}$ ions produced by a laser-induced reaction through an excited state according to $^{40}\mathrm{Ca}$${}^{+}$($4p {}^{2}{P}_{1/2}$) $+$ ${\mathrm{H}}_{2}$ $\ensuremath{\rightarrow}$ $^{40}\mathrm{Ca}$H${}^{+}$ $+$ H $^{40}\mathrm{Ca}$H${}^{+}$ ions stored in a linear Paul trap were characterized by their secular-motion excitation spectrum and by the modified fluorescence images of crystallized Ca${}^{+}$ ions The number of two-species crystallized ions, the secular motion temperature, and the structure were determined by molecular dynamics simulations Both the observed two-species ion crystals and simulation images demonstrate that the CaH${}^{+}$ ions were sympathetically crystallized with their secular-motion temperature being less than 10 mK We determined reaction rates from fluorescence images of two-species Coulomb crystals by systematically changing the reaction time In addition a lower limit for the reaction rate coefficient $k=8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}$ cm${}^{3}$/s was obtained

Angular correlation between Auger electrons successively emitted from photoexcited resonances in Kr and Xe

Abstract: We have studied angular correlations between resonant Auger electrons and successive second-step Auger electrons emitted in a cascade decay after photoexcitation of resonances 3d −1 5/2 5p in Kr and 4d −1 5/2 6p in Xe. Two spectrometers were used for the angle-resolved detection of the two electrons in coincidence. Angular correlations for several pairs of strong lines have been measured in both atoms. The experimental results are compared with multiconfiguration Dirac–Fock calculations which include electron correlations in the initial, intermediate and final states of the cascade. In general, good agreement between experiment and theory is obtained.

GaN/AlGaN nanocolumn ultraviolet light-emitting diode using double-Layer graphene as substrate and transparent electrode

Abstract: The many outstanding properties of graphene have impressed and intrigued scientists for the last few decades. Its transparency to light of all wavelengths combined with a low sheet resistance makes it a promising electrode material for novel optoelectronics. So far, no one has utilized graphene as both the substrate and transparent electrode of a functional optoelectronic device. Here, we demonstrate the use of double-layer graphene as a growth substrate and transparent conductive electrode for an ultraviolet light-emitting diode in a flip-chip configuration, where GaN/AlGaN nanocolumns are grown as the light-emitting structure using plasma-assisted molecular beam epitaxy. Although the sheet resistance is increased after nanocolumn growth compared with pristine double-layer graphene, our experiments show that the double-layer graphene functions adequately as an electrode. The GaN/AlGaN nanocolumns are found to exhibit a high crystal quality with no observable defects or stacking faults. Room-temperature e...