Property control by elastic strain engineering: Application to graphene

Abstract

Various carbon nanostructures, including graphene, are of great interest nowadays for many applications. It has been shown that graphene has unique physical and mechanical properties and its properties can be controlled by the applied strain. The objective of the present paper is to describe several physical properties of graphene that can be controlled by means of elastic strain engineering. The space of in-plane elastic strain components is divided into regions with different structural configurations and physical properties of graphene. It is shown that a gap in the phonon density of states is observed when graphene is strained close to the appearance of ripples. Sound velocities of unstrained graphene do not depend on the propagation direction but application of strain, apart hydrostatic tension, makes graphene elastically anisotropic. The orientation, amplitude and wavelength of unidirectional ripples in graphene can be controlled by a change in the components of the applied strain.