Enhance stable coupling region of a high-Q WGM up to micrometer

摘要

A configuration to obtain the quasicritical coupling state with an enhanced stable coupling region was proposed and demonstrated experimentally by coupling two perpendicular vector modes in tapered fiber with the whispering gallery mode (WGM) in a microresonator. The observed stable coupling region of the high-Q WGM could be up to 1 lm with reliable polarization stability. This work makes it possible to apply direct laser writing and photolithography to prepare controllable coupling for on-chip ultrahigh-Q WGM microcavities and could also improve the stability of packaged WGM structures, which will be beneficial for WGM-based applications such as narrow-linewidth lasers and configurable microwave photonics. Published under license by AIP Publishing.