Localization to delocalization probed by magnetotransport of hBN/graphene/hBN stacks in the ultra-clean regime

We report on magnetotransport in a high-quality graphene device, which is based on monolayer graphene (Gr) encapsulated by hexagonal boron nitride (hBN) layers, i.e., hBN/Gr/hBN stacks. In the vicinity of the Dirac point, a negative magnetoconductance is observed for high temperatures > similar to 40 K, whereas it becomes positive for low temperatures <= similar to 40 K, which implies an interplay of quantum interferences in Dirac materials. The elastic scattering mechanism in hBN/Gr/hBN stacks contrasts with that of conventional graphene on SiO2, and our ultra-clean graphene device shows nonzero magnetoconductance for high temperatures of up to 300 K.

Automated summary

We report on the magnetotransport characteristics of a high-quality graphene device encapsulated in hexagonal boron nitride layers, showing an interplay of quantum interferences in Dirac materials at different temperatures. The elastic scattering mechanism in the hBN/Gr/hBN stacks contrasts with conventional graphene on SiO2, and our ultra-clean graphene device exhibits nonzero magnetoconductance at high temperatures up to 300 K.