Anisotropic fiber with cylindrical polar axes

Abstract

The newly proposed anisotropic fiber structures with cylindrical polar principal axes appear to be an interesting novel class of special lightguides. In this paper, some interesting results relating to such fibers are derived which, to the knowledge of this author, have not yet been reported in the literature. It is found that, ifn _φc0 (Δ _φ )^1/2>n _zc0(Δ _r )^1/2, TE₀₁ will be the fundament mode with a range of single-mode operation given by 2.61n _zc0 (2Δ _r )^1/2 λ/a<2.61n _φc0(2Δ _φ )^1/2. On the other hand, ifn _zc0 (Δ _r )^1/2>n _φc0(Δ _φ )^1/2, then TM₀₁ becomes the fundamental mode whose single-mode operation range is 2.61n _φc0 (2Δ _φ )^1/2 λ/a<2.61n _zc0(2Δ _r )^1/2.