title: Microcavity confinement based on an anomalous zero group-velocity waveguide mode.
abstract: We propose and demonstrate a mechanism for small-modal-volume high-Q cavities based on an anomalous uniform waveguide mode that has zero group velocity at a nonzero wave vector. In a short piece of a uniform waveguide with a specially designed cross section, light is confined longitudinally by small group-velocity propagation and transversely by a reflective cladding. The quality factor Q is greatly enhanced by the small group velocity for a set of cavity lengths that are separated by approximately pi/k0, where k0 is the longitudinal wave vector for which the group velocity is zero.
authors.affiliation: Center for Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. michel@mit.edu
authors.forename: Mihai
authors.initials: M
authors.lastname: Ibanescu
authors.forename: Steven G
authors.initials: SG
authors.lastname: Johnson
authors.forename: David
authors.initials: D
authors.lastname: Roundy
authors.forename: Yoel
authors.initials: Y
authors.lastname: Fink
authors.forename: J D
authors.initials: JD
authors.lastname: Joannopoulos