Eur. Phys. J. B (2018) 91: 163
https://doi.org/10.1140/epjb/e2018-90055-3

Regular Article

Interaction of longitudinal phonons with discrete breather in strained graphene

¹ Department of Physics, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
² Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
³ Department of Physics, Fuzhou University, Fuzhou 350108, Fujian, P.R. China
⁴ School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
⁵ Institute for Metals Superplasticity Problems, Russian Academy of Sciences, 450001 Ufa, Russia
⁶ National Research Tomsk State University, Lenin Ave, 36, 634050 Tomsk, Russia

^a e-mail: roknabad@um.ac.ir

Received: 4 February 2018
Received in final form: 29 March 2018
Published online: 16 July 2018

Abstract

We numerically analyze the interaction of small-amplitude phonon waves with standing gap discrete breather (DB) in strained graphene. To make the system support gap DB, strain is applied to create a gap in the phonon spectrum. We only focus on the in-plane phonons and DB, so the issue is investigated under a quasi-one-dimensional setup. It is found that, for the longitudinal sound waves having frequencies below 6 THz, DB is transparent and thus no radiation of energy from DB takes place; whereas for those sound waves with higher frequencies within the acoustic (optical) phonon band, phonon is mainly transmitted (reflected) by DB, and concomitantly, DB radiates its energy when interacting with phonons. The latter case is supported by the fact that, the sum of the transmitted and reflected phonon energy densities is noticeably higher than that of the incident wave. Our results here may provide insight into energy transport in graphene when the spatially localized nonlinear vibration modes are presented.