Structure and stability of discrete breather in zigzag and armchair carbon nanotubes

Принята  24 марта 2016
Эта работа написана на английском языке
Цитирование: Y. Doi, A. Nakatani. Structure and stability of discrete breather in zigzag and armchair carbon nanotubes. Письма о материалах. 2016. Т.6. №1. С.49-53
BibTex   https://doi.org/10.22226/2410-3535-2016-1-49-53
Structure and stability of stationary discrete breathers (DBs) in armchair and zigzag carbon nanotubes (CNTs) are investigated numerically. Precise numerical solutions of DB in CNTs are calculated by a numerical method that couples the Newton-Raphson method and molecular dynamics method. Linear stability analysis is performed by constructing of monodromy matrix of the numerical solution of DB from the numerical results of MD simulation. In both structures of zigzag and armchair carbon nanotube, stationary DBs with higher angular frequency above zone boundary mode exist. Displacement of DB is on cylindrical plane of CNTs. Linear stability analysis shows that DBs in both armchair CNT and zigzag CNT are unstable. The maximum growth rate of the unstable perturbation mode can be calculated numerically. The maximum growth rate of armchair CNT is greater than that of zigzag CNT even when the curvature of the cylindrical plane of zigzag CNT is greater than armchair CNT. In both case of armchair and zigzag CNT, the unstable motion is excited in the direction out of the cylindrical plane of CNTs. Unstable dynamics is suppressed by introducing extensive strain in axial direction of CNT. In this case, motion of the unstable perturbation modes is confined on the cylindrical plane of CNTs