Fiber-optic add-drop device based on a silica microsphere-whispering gallery mode system

Abstract

An all-optical passive four-port system including a fused silica microsphere and two tapered fibers is proposed and demonstrated for the application as a channel adding-dropping device. It is shown that channels can be selectively exchanged between two fibers by coupling to a whispering gallery mode resonance in the microsphere. Finesse in excess of 11150 is measured for the loaded whispering gallery modes.