Shubnikov-de Haas measurements on a high mobility monolayer graphene flake sandwiched between boron nitride sheets

J Phys Condens Matter. 2017 Jun 7;29(22):225301. doi: 10.1088/1361-648X/aa6d36. Epub 2017 Apr 13.

Abstract

A flake of monolayer graphene was sandwiched between boron nitride sheets. Temperature dependent Shubnikov-de Haas measurements were performed to access how this technique influences the electronic properties of the graphene sample. The maximum mobility found in this configuration was approximately 105 cm2 Vs -1. From the phase of the oscillations a Berry phase β of 1/2 was obtained indicating the presence of Dirac fermions. We obtained Fermi velocities around [Formula: see text] m s-1 which imply hopping energies close to 2.5 eV. Furthermore, the carrier lifetime is typically higher than that found in graphene supported by SiO2, reaching values higher than 700 fs.