Strain controlled faceted bubbles in supported graphene

Graphene samples supported on a substrate often exhibit out-of-plane deformations with different features and origins. In the process of synthesising graphene by chemical vapor deposition), network of localized wrinkles are observed upon cooling of graphene. Graphene bubbles are observed with various shapes and sizes, induced by gas trapped between graphene and substrate. Such wrinkles and bubbles are known to affect the electronic properties of graphene. There is an increasing interest in experimentally controlling their emergence and morphology. However, the theoretical understanding of mechanisms behind various out-of-plane deformations in supported graphene remains incomplete. We systematically study the wrinkling networks and various shapes of bubbles on supported graphene upon compressive stress. We build a strain-gass phase diagram to present how the shape of the bubble can be influenced by applied strain, and trapped gass pressure. We identify that the compressive circumferential strain on the circle of the bubble triggers short wrinkles and promotes the transition to a faceted bubble. Our studies on controlling the formation of wrinkles and faceted bubbles could offer potential applications in strain engineering of supported graphene