Splicing of single polarization-maintaining fibers

Splicing characteristics of single polarization-maintaining fibers with the stress-induced birefringence is presented using a new method for aligning principal axes of the refractive-index ellipsoid. Crosstalk degradations caused by the transverse displacements for fiber splicing are small, while the rotational misalignments strongly affect the crosstalk. The alignment method consists of butting the convex profiles of the stress-induced regions, whose profiles are prepared by the mesa etching. Resultant splicing coupling loss is 0.15 dB and the crosstalk changes from -29 to -27 dB as the best result. Fiber-length dependence of the crosstalk degradation produced by splicing is discussed.