Giant auxetic behaviour in engineered graphene

Abstract

Graphene monolayers engineered to adopt a corrugated conformation are found to exhibit very pronounced lateral expansion characteristics upon uniaxial stretching in specific directions, i.e. giant negative Poisson’s ratio (auxeticity). Such anomalous properties are manifested in-plane and may be controlled through the shape and amplitude of the wave-like pattern of the corrugation, which in the case of graphene may be controlled through the introduction of patterned ‘defects’. This confirms that auxeticity via corrugation can be achieved even at the nanoscale, as demonstrated here for graphene with patterned ‘defects’, suggesting that this mechanism should be operational at different scales of structures, thus providing a new blueprint for the design or manufacture of auxetic materials and metamaterials which can have tailor-made giant negative Poisson’s ratio properties.