Two-dimensional Bose-Hubbard model for helium on graphene

Jiangyong Yu, Ethan Lauricella, Mohamed Elsayed, Kenneth Shepherd Jr., Nathan S. Nichols, 2 Todd Lombardi, Sang Wook Kim, Carlos Wexler, Juan M. Vanegas, Taras Lakoba, Valeri N. Kotov, and Adrian Del Maestro 6, 1 Department of Physics, University of Vermont, Burlington, VT 05405, USA Materials Science Program, University of Vermont, Burlington, VT 05405,USA Department of Physics and Astronomy, University of Missouri, Columbia, MO 65211, USA Department of Mathematics & Statistics, University of Vermont, Burlington, VT 05405, USA Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, USA Min H. Kao Department of Electrical Engineering and Computer Science, University of Tennessee, Knoxville, TN 37996, USA