Cladding mode resonances in short- and long- fiber grating filters: comment.
To obtain the coupling constant for core-mode-cladding-mode coupling, it is necessary to calculate the total power carried by the cladding mode, and the related formulas are given by T. Erdogan [J. Opt. Soc. Am. A14, 1773 (1997)] and [J. Opt. Soc. Am. A17, 2113 (2000)]. I found that my formulas for P1 and P3 are the same as Eqs. (B2) and (B16) in the 1997 paper, but Eqs. (B3)-(B15) for P2 are worth commenting on, and this comment gives our derivations.
Yuan
Yinquan
Y
Ministry of Education, Key Laboratory of Fiber Optic Sensing Technology and Information Processing, Wuhan University of Technology, Wuhan 430070, China. ymyyq@whut.edu.cn