Growth of quantum three-dimensional structure of InGaAs emitting at ~1 µm applicable for a broadband near-infrared light source

We obtained a high-intensity and broadband emission centered at ~1 µm from InGaAs quantum three-dimensional (3D) structures grown on a GaAs substrate using molecular beam epitaxy. An InGaAs thin layer grown on GaAs with a thickness close to the critical layer thickness is normally affected by strain as a result of the lattice mismatch and introduced misfit dislocations. However, under certain growth conditions for the In concentration and growth temperature, the growth mode of the InGaAs layer can be transformed from two-dimensional to 3D growth. We found the optimal conditions to obtain a broadband emission from 3D structures with a high intensity and controlled center wavelength at ~1 µm. This method offers an alternative approach for fabricating a broadband near-infrared light source for telecommunication and medical imaging systems such as for optical coherence tomography

Attempts to create a cooperative institutional repository : HARP (Hiroshima Associated Repository Portal)

研究機関における機関リポジトリ構築はオープンアクセス普及のための重要な選択肢として認識され大規模大学を中心に普及しつつあるが,その構築には一定水準以上の技術と少なくない費用が必要となる。これは特に中・小規模機関で機関リポジトリを構築する際の障壁となっている。2006 年より実験を始め,2008 年4月に運用を開始した広島県大学共同リポジトリの立上げの経緯を報告することで,複数機関による共同でのリポジトリ構築という手法が中・小規模機関での機関リポジトリの立ち上げに有効であることを示す。Building an institutional repository is seen as an effective means for large-scale universities tospread open access, but it requires considerable cost and expertise. It is this cost and technical expertisethat has become barrier in constructing repositories, particularly for small and medium institutions. Byreporting on the details of the process of bringing up the Hiroshima Associated Repository Portal, one ofthe pioneer efforts of a shared repository in Japan, we believe we can show that the technique of sharinga repository among several institutions can be an effective means for small and medium sized institutionsto bring up an institutional repository

Finite element analysis of damage-healring behaviour in self-healing ceramic materials

In this study, we develop the constitutive model to analyse the self-healing ceramic materials within the framework of FEM. The self-hearing and isotropic damage constitutive model for ceramic materials can describe not only the damage process under a certain boundary condition, but also the self-healing process under a high-temperature condition. The damage process is formulated based on the fracture mechanics, and the self-healing process is formulated based on the kinetic model of self-healing time and velocity. Then, we apply the proposed model to analyses of homogeneous ceramic materials and unit cell model of fiberreinforced ceramic material

Growth of quantum three-dimensional structure of InGaAs emitting at ~1 µm applicable for a broadband near-infrared light source

We obtained a high-intensity and broadband emission centered at ~1 µm from InGaAs quantum three-dimensional (3D) structures grown on a GaAs substrate using molecular beam epitaxy. An InGaAs thin layer grown on GaAs with a thickness close to the critical layer thickness is normally affected by strain as a result of the lattice mismatch and introduced misfit dislocations. However, under certain growth conditions for the In concentration and growth temperature, the growth mode of the InGaAs layer can be transformed from two-dimensional to 3D growth. We found the optimal conditions to obtain a broadband emission from 3D structures with a high intensity and controlled center wavelength at ~1 µm. This method offers an alternative approach for fabricating a broadband near-infrared light source for telecommunication and medical imaging systems such as for optical coherence tomography