Strains and pseudomagnetic fields in circular graphene rings

We demonstrate that a circular graphene ring under a shear stress displays strong pseudomagnetic fields. We calculate the pseudomagnetic field both from continuum elasticity theory as well as molecular-dynamics simulations. Stable wrinkles are induced by shear deformations and lead to enhancement of the pseudomagnetic field. The strong pseudomagnetic field found here can be observed by imaging a graphene flake at the atomic level, e.g., through a scanning tunneling microscope.