title: Magnitude and Origin of Electrical Noise at Individual Grain Boundaries in Graphene.
abstract: Grain boundaries (GBs) are undesired in large area layered 2D materials as they degrade the device quality and their electronic performance. Here we show that the grain boundaries in graphene which induce additional scattering of carriers in the conduction channel also act as an additional and strong source of electrical noise especially at the room temperature. From graphene field effect transistors consisting of single GB, we find that the electrical noise across the graphene GBs can be nearly 10 000 times larger than the noise from equivalent dimensions in single crystalline graphene. At high carrier densities (n), the noise magnitude across the GBs decreases as ∝1/n, suggesting Hooge-type mobility fluctuations, whereas at low n close to the Dirac point, the noise magnitude could be quantitatively described by the fluctuations in the number of propagating modes across the GB.
authors.affiliation: Department of Physics, ‡Department of Materials Engineering, §Materials Research Center, and ∥Centre for Nano Science and Engineering, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Vidya
authors.initials: V
authors.lastname: Kochat
authors.affiliation: Department of Physics, ‡Department of Materials Engineering, §Materials Research Center, and ∥Centre for Nano Science and Engineering, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Chandra Sekhar
authors.initials: CS
authors.lastname: Tiwary
authors.affiliation: Department of Physics, ‡Department of Materials Engineering, §Materials Research Center, and ∥Centre for Nano Science and Engineering, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Tathagata
authors.initials: T
authors.lastname: Biswas
authors.affiliation: Department of Physics, ‡Department of Materials Engineering, §Materials Research Center, and ∥Centre for Nano Science and Engineering, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Gopalakrishnan
authors.initials: G
authors.lastname: Ramalingam
authors.affiliation: Department of Physics, ‡Department of Materials Engineering, §Materials Research Center, and ∥Centre for Nano Science and Engineering, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Hsieh
authors.affiliation: Department of Physics, ‡Department of Materials Engineering, §Materials Research Center, and ∥Centre for Nano Science and Engineering, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Kamanio
authors.initials: K
authors.lastname: Chattopadhyay
authors.affiliation: Department of Physics, ‡Department of Materials Engineering, §Materials Research Center, and ∥Centre for Nano Science and Engineering, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Raghavan
authors.affiliation: Department of Physics, ‡Department of Materials Engineering, §Materials Research Center, and ∥Centre for Nano Science and Engineering, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Manish
authors.initials: M
authors.lastname: Jain
authors.affiliation: Department of Physics, ‡Department of Materials Engineering, §Materials Research Center, and ∥Centre for Nano Science and Engineering, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Arindam
authors.initials: A
authors.lastname: Ghosh
keywords: 1/f noise; CVD graphene; Hooge model; grain boundary; transmission probability