Electron-hole asymmetric magnetotransport of graphene-colloidal quantum dot device

Abstract

Interfacing graphene with other low-dimensional material has gained attentions recently due to its potential to stimulate new physics and device innovations for optoelectronic and electronic applications. Here, we exploit a solution-processed approach to introduce colloidal quantum dot (CQD) to the bilayer graphene device. The magnetotransport properties of the graphene device is drastically altered due to the presence of the CQD potential, leading to the observation of AB-like oscillation in the quantum Hall regime and screening of the intervalley scattering. The anomalous magnetotransport behavior is attributed to the coulombic scattering introduced by the CQDs and is shown to be highly asymmetric depending on the polarity of the transport carriers. These results prove the potential of such flexible method for engineering microscopic scattering process and performance of the graphene device that may lead to intriguing device application in such hybrid system.