Papers by Author: Yusuke Kinoshita

Abstract: Using the first-principles calculation, the elastic constant C44 of Ag/Al multilayers with different modulation periods from 0.43 nm to 2.27 nm has been evaluated in order to examine the effect of atomic and electronic structures on it. With increasing modulation period, C44 decreases and becomes close to that obtained by the conventional mixing rule, however, the difference of 8 % still remains at the modulation period of 2.27 nm. As C44 correlates with the average interplanar spacing, the decrease of C44 can be explained by the decrease of the charge density in the stacking direction due to the increase of the average interplanar spacing. The difference in the electronic structure is included in the effect of atomic structure.

Abstract: Carbon nanotubes (CNTs) have been attracting attention because of their prominent mechanical and electronic properties. In this study, we investigate the deformation of a single-walled carbon nanotube (SWCNT) with a bend junction using atomistic modeling with Brenner potential to analyze strain concentration caused by macroscopic tube shape and microscopic interatomic bond structure. The simulation model consists of (8,8) and (14,0) CNTs connected with a flexion angle of 30 degrees. For geometric reasons five and seven-membered rings are introduced at the inside and outside of the bend junction. After the structure under no external load is determined, tensile load is applied to the model. Then, we analyze the strain concentration at the bend junction, and high tensile strain is observed at the inside of the bend junction. The strain at the seven-membered ring at the inside of the bend junction has higher strain compared to the neighboring rings due to the microscopic effect.