Dual-gated bilayer graphene hot-electron bolometer.
Graphene is an attractive material for use in optical detectors because it absorbs light from mid-infrared to ultraviolet wavelengths with nearly equal strength. Graphene is particularly well suited for bolometers-devices that detect temperature-induced changes in electrical conductivity caused by the absorption of light-because its small electron heat capacity and weak electron-phonon coupling lead to large light-induced changes in electron temperature. Here, we demonstrate a hot-electron bolometer made of bilayer graphene that is dual-gated to create a tunable bandgap and electron-temperature-dependent conductivity. The bolometer exhibits a noise-equivalent power (33 fW Hz(-1/2) at 5 K) that is several times lower, and intrinsic speed (>1 GHz at 10 K) three to five orders of magnitude higher than commercial silicon bolometers and superconducting transition-edge sensors at similar temperatures.
Center for Nanophysics and Advanced Materials and Materials Research Science and Engineering Center, University of Maryland, College Park, MD 20742, USA.
Jun
J
Yan
M-H
MH
Kim
J A
JA
Elle
A B
AB
Sushkov
G S
GS
Jenkins
H M
HM
Milchberg
M S
MS
Fuhrer
H D
HD
Drew
D004553:Electric Conductivity; D004583:Electrons; D006108:Graphite / Q000737:chemistry*; D008027:Light; D049329:Nanostructures / Q000737:chemistry*; D060739:Phonons; D013499:Surface Properties; D013696:Temperature; D013814:Thermal Conductivity
D006108:Graphite