  One- and two-layer graphene have recently been shown to feature new physical
phenomena such as unconventional quantum Hall effects and prospects of
supporting a non-silicon technological platform using epitaxial graphene. While
both one- and two-layer graphene have been studied extensively, continuous
sheets of graphene possessing both parts have not yet been explored. Here we
report a study of such graphene hybrid structures. In a bulk hybrid featuring
two large-area one- and two-layer graphene and an interface between them, two
sets of Landau levels and features related to the interface were found. In edge
hybrids featuring a large two-layer graphene with narrow one-layer graphene
edges, we observed an anomalous suppression in quantum oscillation amplitude
due to the locking of one- and two-layer graphene Fermi energies and emergent
chiral interface states. These findings demonstrate the importance of these
hybrid structures whose unique interface states and related phenomena deserve
further studies.

Mesoscale and Nanoscale Physics;Materials Science