04 July 2014
Vol 345, Issue 6192

About The Cover

Cover image expansion

COVER Artist's view of a bilayer of graphene, in which two hexagonal carbon lattices are stacked on top of each other. The unusual band structure of bilayer graphene, coupled with external fields and interactions between electrons, leads to exotic quantum effects. See pages 31, 55, 58, and 61.
Image: C. Bickel/Science