Large, non-saturating magnetoresistance in single layer chemical vapor deposition graphene with an h-BN capping layer

Abstract

We report large, non-saturating magnetoresistance (MR) of ∼140% in single layer chemical vapor deposition (CVD) graphene with an h-BN capping layer at room temperature at B = 9 T. Based on the classical model developed by Parish and Littlewood, our results show that the MR is proportional to the average mobility <μ > and decreases with increasing temperature. In contrast, in a large-area, extremely homogenous single layer epitaxial graphene (EG) device, the MR is saturating and is inversely proportional to <μ>, which is consistent with the finite resistance network picture. By comparing the results obtained from CVD graphene with an h-BN capping layer with those from the EG device, we show that the non-saturating linear characteristics come from multi-channel current paths in a two-dimensional plane due to the intrinsic grain boundaries and domains of CVD graphene by capping an h-BN layer that increase the <μ> of CVD graphene. Our results on CVD graphene with an h-BN capping layer pave the way for industrial schemes of graphene-based and air-stable magnetic field sensors with a linear, large response at room temperature.