title: Ultralow mode-volume photonic crystal nanobeam cavities for high-efficiency coupling to individual carbon nanotube emitters.
abstract: The unique emission properties of single-walled carbon nanotubes are attractive for achieving increased functionality in integrated photonics. In addition to being room-temperature telecom-band emitters that can be directly grown on silicon, they are ideal for coupling to nanoscale photonic structures. Here we report on high-efficiency coupling of individual air-suspended carbon nanotubes to silicon photonic crystal nanobeam cavities. Photoluminescence images of dielectric- and air-mode cavities reflect their distinctly different mode profiles and show that fields in the air are important for coupling. We find that the air-mode cavities couple more efficiently, and estimated spontaneous emission coupling factors reach a value as high as 0.85. Our results demonstrate advantages of ultralow mode-volumes in air-mode cavities for coupling to low-dimensional nanoscale emitters.
authors.affiliation: Institute of Engineering Innovation, The University of Tokyo, Tokyo 113-8656, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Miura
authors.affiliation: Institute of Engineering Innovation, The University of Tokyo, Tokyo 113-8656, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Imamura
authors.affiliation: Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Ohta
authors.affiliation: Institute of Engineering Innovation, The University of Tokyo, Tokyo 113-8656, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Ishii
authors.affiliation: Institute of Engineering Innovation, The University of Tokyo, Tokyo 113-8656, Japan.
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.affiliation: Institute of Engineering Innovation, The University of Tokyo, Tokyo 113-8656, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Shimada
authors.affiliation: Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Iwamoto
authors.affiliation: Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Arakawa
authors.affiliation: Institute of Engineering Innovation, The University of Tokyo, Tokyo 113-8656, Japan.
authors.forename: Y K
authors.initials: YK
authors.lastname: Kato