Microsphere resonator mode characterization by pedestal anti-resonant reflecting waveguide coupler

The stripline pedestal anti-resonant reflecting optical waveguide (SPARROW) is an efficient and robust coupling device for silica microsphere whispering-gallery-mode excitation. The concept incorporates alternating layers of Si and SiO/sub 2/, designed to isolate the mode of the sphere and the waveguide from the dielectric substrate. Experimental characterizations of this coupling technique are presented, including displacement measurements, and whispering-gallery-mode intensity mapping. Power extraction efficiencies of over 98% are reported.