title: Graphene-based mid-infrared room-temperature pyroelectric bolometers with ultrahigh temperature coefficient of resistance.
abstract: There is a growing number of applications demanding highly sensitive photodetectors in the mid-infrared. Thermal photodetectors, such as bolometers, have emerged as the technology of choice, because they do not need cooling. The performance of a bolometer is linked to its temperature coefficient of resistance (TCR, ∼2-4% K-1for state-of-the-art materials). Graphene is ideally suited for optoelectronic applications, with a variety of reported photodetectors ranging from visible to THz frequencies. For the mid-infrared, graphene-based detectors with TCRs ∼4-11% K-1have been demonstrated. Here we present an uncooled, mid-infrared photodetector, where the pyroelectric response of a LiNbO3crystal is transduced with high gain (up to 200) into resistivity modulation for graphene. This is achieved by fabricating a floating metallic structure that concentrates the pyroelectric charge on the top-gate capacitor of the graphene channel, leading to TCRs up to 900% K-1, and the ability to resolve temperature variations down to 15 μK.
authors.affiliation: Cambridge Graphene Centre, University of Cambridge, Cambridge CB3 0FA, UK.
authors.forename: U
authors.initials: U
authors.lastname: Sassi
authors.affiliation: ICFO Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Barcelona, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Parret
authors.affiliation: ICFO Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Barcelona, Spain.
authors.forename: S
authors.identifier: 0000-0002-3185-1583
authors.initials: S
authors.lastname: Nanot
authors.affiliation: Nokia Technologies, Broers Building, Cambridge CB3 0FA, UK.
authors.forename: M
authors.initials: M
authors.lastname: Bruna
authors.affiliation: Nokia Technologies, Broers Building, Cambridge CB3 0FA, UK.
authors.forename: S
authors.initials: S
authors.lastname: Borini
authors.affiliation: Cambridge Graphene Centre, University of Cambridge, Cambridge CB3 0FA, UK.
authors.forename: D
authors.initials: D
authors.lastname: De Fazio
authors.affiliation: Cambridge Graphene Centre, University of Cambridge, Cambridge CB3 0FA, UK.
authors.forename: Z
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: Department of Materials Science and Engineering, University of Ioannina, Ioannina 45110, Greece.
authors.forename: E
authors.initials: E
authors.lastname: Lidorikis
authors.affiliation: ICFO Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Barcelona, Spain.|ICREA Institució Catalana de Recerça i Estudis Avancats, Barcelona 08010, Spain.
authors.forename: F H L
authors.initials: FH
authors.lastname: Koppens
authors.affiliation: Cambridge Graphene Centre, University of Cambridge, Cambridge CB3 0FA, UK.
authors.forename: A C
authors.initials: AC
authors.lastname: Ferrari
authors.affiliation: Emberion Ltd, Sheraton House, Castle Park, Cambridge CB3 0AX, UK.
authors.forename: A
authors.initials: A
authors.lastname: Colli