We have numerically studied a taper-microsphere coupling system with coupled-mode theory by introducing a mode-coupling mechanism. Transmission and reflection coefficients have been obtained directly through numerical calculation for a spherical silica microcavity. In the presence of the modal coupling mechanism, the optimal condition for transferring the light energy into the microsphere is no longer the critical coupling point. Instead, it should be in the under-coupling regime and can be reached by optimizing the size of the fiber taper and the taper-microsphere gap.
© 2008 Optical Society of America
Fiber Optics and Optical Communications
Original Manuscript: July 14, 2008
Revised Manuscript: August 30, 2008
Manuscript Accepted: September 9, 2008
Published: October 27, 2008
Chang-Ling Zou, Yong Yang, Chun-Hua Dong, Yun-Feng Xiao, Xiao-Wei Wu, Zheng-Fu Han, and Guang-Can Guo, "Taper-microsphere coupling with numerical calculation of coupled-mode theory," J. Opt. Soc. Am. B 25, 1895-1898 (2008)