title: Graphene-contact electrically driven microdisk lasers.
abstract: Active nanophotonic devices are attractive due to their low-power consumption, ultrafast modulation speed and high-density integration. Although electrical operation is required for practical implementation of these devices, it is not straightforward to introduce a proper current path into such a wavelength-scale nanostructure without affecting the optical properties. For example, to demonstrate electrically driven nanolasers, complicated fabrication techniques have been used thus far. Here we report an electrically driven microdisk laser using a transparent graphene electrode. Current is injected efficiently through the graphene sheet covering the top surface of the microdisk cavity, and, for the first time, lasing operation was achieved with a low-threshold current of ~300 μA at room temperature. In addition, we measured significant electroluminescence from a graphene-contact subwavelength-scale single nanopillar structure. This work represents a new paradigm for the practical applications of integrated photonic systems, by conformally mounting graphene on the complex surfaces of non-planar three-dimensional nanostructures.
authors.affiliation: Department of Physics, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: Yoon-Ho
authors.initials: YH
authors.lastname: Kim
authors.forename: Soon-Hong
authors.initials: SH
authors.lastname: Kwon
authors.forename: Jung Min
authors.initials: JM
authors.lastname: Lee
authors.forename: Min-Soo
authors.initials: MS
authors.lastname: Hwang
authors.forename: Ju-Hyung
authors.initials: JH
authors.lastname: Kang
authors.forename: Won Il
authors.initials: WI
authors.lastname: Park
authors.forename: Hong-Gyu
authors.initials: HG
authors.lastname: Park