title: Optimizing broadband terahertz modulation with hybrid graphene/metasurface structures.
abstract: We demonstrate efficient terahertz (THz) modulation by coupling graphene strongly with a broadband THz metasurface device. This THz metasurface, made of periodic gold slit arrays, shows near unity broadband transmission, which arises from coherent radiation of the enhanced local-field in the slits. Utilizing graphene as an active load with tunable conductivity, we can significantly modify the local-field enhancement and strongly modulate the THz wave transmission. This hybrid device also provides a new platform for future nonlinear THz spectroscopy study of graphene.
authors.affiliation: Department of Physics, University of California at Berkeley , Berkeley, California 94720, United States.
authors.forename: S-F
authors.initials: SF
authors.lastname: Shi
authors.forename: B
authors.initials: B
authors.lastname: Zeng
authors.forename: H-L
authors.initials: HL
authors.lastname: Han
authors.forename: X
authors.initials: X
authors.lastname: Hong
authors.forename: H-Z
authors.initials: HZ
authors.lastname: Tsai
authors.forename: H S
authors.initials: HS
authors.lastname: Jung
authors.forename: A
authors.initials: A
authors.lastname: Zettl
authors.forename: M F
authors.initials: MF
authors.lastname: Crommie
authors.forename: F
authors.initials: F
authors.lastname: Wang
keywords: Metasurface; graphene; local-field; modulation; terahertz