Topography

1. New Dirac points in graphene with a periodic potentialBrian J. LeRoy, University of Arizona, DMR 0953784 • The electronic properties of graphene devices are strongly affected by the substrate under the graphene. We have measured the electronic properties of graphene on boron nitride. We have observed the following phenomena. • A moiré pattern due to the misalignment between the graphene and boron nitride lattices. • The moiré pattern creates a periodic potential which creates new superlattice Dirac points. • Long wavelength oscillations of the density of states near buried step edges. • Using boron nitride as a substrate for graphene promises many new discoveries because of the ability to control the electrons in graphene. Topography Band Diagram STM Spectroscopy Dirac point Superlattice Dirac points Xue, BJL et al., PRL 108, 016801 (2012); Yankowitz, BJL et al., Nat. Phys. 8, 382 (2012)

2. New Dirac points in graphene with a periodic potentialBrian J. LeRoy, University of Arizona, DMR 0953784 • Graphene holds great promise for new electronic devices which may replace silicon. • This award supports work with the Physics Factory which is a local non-profit group to create new nanoscience demonstrations which will be used in trips to local K-12 schools. The grant is supporting 2 undergraduate students to who are creating demonstrations related to the research. • A female Hispanic REU student from the University of Texas-El Paso was supported by the grant during the summer of 2012. A student and mentor work on the construction of a demonstration.