1211.0355 (S. J. Woo et al.)

Ideal Strength of Doped Graphene    [PDF]

S. J. Woo, Young-Woo Son

While the mechanical distortions change the electronic properties of graphene significantly, the effects of electronic manipulation on its mechanical properties have not been known. Using ab initio pseudopotential calculations, we have studied the effect of charge doping on the ideal strength of graphene. When graphene expands isotropically under equibiaxial strain, both the electron and hole doping can maintain or improve the ideal strength of graphene slightly while the doping induces a dramatic enhancement of the corresponding critical breaking strain. Contrary to the equibiaxial strain case, the electron doping decreases the ideal strength as well as critical strain of uniaxially strained graphene while the hole doping increases the both. Origins of mechanical failure are shown to depend on the type of applied external strains resulting in different behaviors of ideal strength of graphene upon doping. Our findings may resolve a recent contradiction between theoretical and experimental results on the ideal strength of graphene.

View original: http://arxiv.org/abs/1211.0355