title: Single-input spherical microbubble resonator.
abstract: A single-input whispering gallery optical microbubble resonator is presented. Spherical microbubbles with diameters less than 100 μm, micrometer-sized wall thicknesses, and a single opening or input were fabricated by heating the tapered tip of a pressurized glass capillary using a CO(2) laser. Optical whispering gallery modes with Q factors of ∼10(5) were obtained. The bubbles were filled with water and mode shifts of ∼20 GHz were observed. Fano-type resonances were detected when the coupling optical fiber diameter was less than 1 μm, causing the microresonator to switch from being a band-stop filter to a bandpass filter. Larger bubbles with submicrometer wall thickness were also fabricated.
authors.affiliation: Physics Department, University College Cork, Cork, Ireland. amy.watkins@tyndall.ie
authors.forename: Amy
authors.initials: A
authors.lastname: Watkins
authors.forename: Jonathan
authors.initials: J
authors.lastname: Ward
authors.forename: Yuqiang
authors.initials: Y
authors.lastname: Wu
authors.forename: Síle Nic
authors.initials: SN
authors.lastname: Chormaic