Abstract
We demonstrate a low-loss, optical four port resonant coupler (add-drop geometry), using ultrahigh () toroidal microcavities. Different regimes of operation are investigated by variation of coupling between resonator and fiber taper waveguides. As a result, waveguide-to-waveguide power transfer efficiency of 93% (0.3 dB loss) and nonresonant insertion loss of 0.02% () for narrow bandwidth (57 MHz) four port couplers are achieved in this work. The combination of low-loss, fiber compatibility, and wafer-scale design would be suitable for a variety of applications ranging from quantum optics to photonic networks.
- Received 2 December 2003
DOI:https://doi.org/10.1103/PhysRevLett.92.253905
©2004 American Physical Society