Analytical expression of confinement loss in Bragg fibers and its relationship with generalized quarter-wave stack condition

作者：Sakai Jun ichi^*

来源：Journal of the Optical Society of America B-Optical Physics, 2011, 28(11): 2740-2754.

DOI：10.1364/JOSAB.28.002740

Analytical expression of confinement loss (CL) is presented for the TE mode of Bragg fibers by applying the perturbation theory to electromagnetic fields under an asymptotic expansion approximation. The expression can be used to evaluate CL for general cases as well as the quarter-wave stack (QWS) condition. Under the generalized QWS condition, the expression gives an explicit dependence of CL on the fiber structural parameters, the number of periodic layer pairs, and so on. We also present numerical results for dependence of the CL on various parameters, such as the core radius, the cladding layer thicknesses, the refractive indices, the wavelengths, the number of periodic layer pairs, and the mode number. The relation between the CL and the generalized QWS condition is scrutinized. The position of the minimum CL corresponds well to the condition satisfying a generalized QWS condition.

• 出版日期2011-11