title: Determination of the Thermal Noise Limit of Graphene Biotransistors.
abstract: To determine the thermal noise limit of graphene biotransistors, we have measured the complex impedance between the basal plane of single-layer graphene and an aqueous electrolyte. The impedance is dominated by an imaginary component but has a finite real component. Invoking the fluctuation-dissipation theorem, we determine the power spectral density of thermally driven voltage fluctuations at the graphene/electrolyte interface. The fluctuations have 1/f(p) dependence, with p = 0.75-0.85, and the magnitude of fluctuations scales inversely with area. Our results explain noise spectra previously measured in liquid-gated suspended graphene devices and provide realistic targets for future device performance.
authors.affiliation: †Department of Physics, Linfield College, McMinnville, Oregon 97128, United States.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Crosser
authors.affiliation: ‡Department of Physics, Oregon State University, Corvallis, Oregon 97331, United States.
authors.forename: Morgan A
authors.initials: MA
authors.lastname: Brown
authors.affiliation: §Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States.
authors.forename: Paul L
authors.initials: PL
authors.lastname: McEuen
authors.affiliation: ‡Department of Physics, Oregon State University, Corvallis, Oregon 97331, United States.
authors.forename: Ethan D
authors.initials: ED
authors.lastname: Minot
mesh_terms: D015374:Biosensing Techniques; D017097:Electric Impedance; D004573:Electrolytes / Q000737:chemistry; D004867:Equipment Design; D006108:Graphite / Q000737:chemistry*; D013696:Temperature; D014173:Transistors, Electronic
chemical_list: D004573:Electrolytes; D006108:Graphite
keywords: 1/f noise; Graphene field-effect transistor; biosensor; liquid gate; noise