Phonon Dissipation of Atomic-Scale Fatigue in Phosphorene with Zigzag and Armchair Directions

Abstract

Herein, we explore the low-cycle fatigue properties of phosphorene in the zigzag and armchair directions as well as their phonon energy dissipation. The results indicate that the armchair direction of phosphorene possesses a fatigue life higher than that of the zigzag direction. Moreover, the fatigue life is negatively correlated with both excitation frequency and excitation amplitude. The phenomenon of stress accumulation occurs during the fatigue process until the interatomic bonds break to produce cracks. In addition, the stress accumulation efficiency rises as the excitation frequency increases, and the fatigue life is lower. As the excitation frequency and excitation amplitude increase, the number of in-plane acoustic modes increases, generating new energy dissipation channels; more energy-carrying phonons are excited, which ultimately leads to higher energy dissipation efficiency and therefore lower fatigue life.