title: Noise in Graphene Superlattices Grown on Hexagonal Boron Nitride.
abstract: Existing in almost all electronic systems, the current noise spectral density, originated from the fluctuation of current, is by nature far more sensitive than the mean value of current, the most common characteristic parameter in electronic devices. Existing models on its origin of either carrier number or mobility are adopted in practically all electronic devices. For the past few decades, there has been no experimental evidence for direct association between 1/f noise and any other kinetic phenomena in solid state devices. Here, in the study of a van der Waals heterostructure of graphene on hexagonal BN superlattice, satellite Dirac points have been characterized through 1/f noise spectral density with pronounced local minima and asymmetric magnitude associated with its unique energy dispersion spectrum, which can only be revealed by scanning tunneling microscopy and low temperature magneto-transport measurement. More importantly, these features even emerge in the noise spectra of devices showing no minima in electric current, and are robust at all temperatures down to 4.3 K. In addition, graphene on h-BN exhibits a record low noise level of 1.6 × 10(-9) μm(2) Hz(-1) at 10 Hz, more than 1 order of magnitude lower than previous results for graphene on SiO2. Such an epitaxial van der Waals material system not only enables an unprecedented characterization of fundamentals in solids by 1/f noise, but its superior interface also provides a key and feasible solution for further improvement of the noise level for graphene devices.
authors.affiliation: Wuhan National High Magnetic Field Center and School of Electrical and Electronic Engineering, Huazhong University of Science and Technology , Wuhan 430074, China.
authors.forename: Xuefei
authors.initials: X
authors.lastname: Li
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Lu
authors.affiliation: Wuhan National High Magnetic Field Center and School of Electrical and Electronic Engineering, Huazhong University of Science and Technology , Wuhan 430074, China.
authors.forename: Tiaoyang
authors.initials: T
authors.lastname: Li
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Yang
authors.affiliation: Wuhan National High Magnetic Field Center and School of Electrical and Electronic Engineering, Huazhong University of Science and Technology , Wuhan 430074, China.
authors.forename: Jianming
authors.initials: J
authors.lastname: Fang
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Guangyu
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Wuhan National High Magnetic Field Center and School of Electrical and Electronic Engineering, Huazhong University of Science and Technology , Wuhan 430074, China.
authors.forename: Yanqing
authors.initials: Y
authors.lastname: Wu
keywords: boron nitride; graphene; low frequency noise; superlattice; transistor