Anisotropic Optical Fibers Research Articles

Degree of polarization including the random-mode-conversion effect in anisotropic single-mode optical fibers: errata

Get PDF Email Share Share with Facebook Tweet This Post on reddit Share with LinkedIn Add to CiteULike Add to Mendeley Add to BibSonomy Get Citation Copy Citation Text Jun-ichi Sakai, "Degree of polarization including the random-mode-conversion effect in anisotropic single-mode optical fibers: errata," J. Opt. Soc. Am. A 2, 483-483 (1985) Export Citation BibTex Endnote (RIS) HTML Plain Text Citation alert Save article

Degree of polarization including the random-mode-conversion effect in anisotropic single-mode optical fibers

A theory concerning the degree of polarization in anisotropic single-mode fibers has been developed that takes into account random mode conversion along the fiber. This mode-conversion effect is treated statistically by using an autocorrelation function and the mean square of the random perturbation. The degree of polarization is given explicitly in terms of the incident-polarization condition, the degree of coherence, the fiber parameters, the mode-coupling coefficients, and the randomness statistical parameters. This degree of polarization is degraded, even for eigenpolarization excitation, if mode conversion takes place randomly. When random mode conversion is present, the degree of polarization takes on a nonzero value for any fiber position and for any incident-polarization condition. Moreover, a numerical calculation reveals that a twisted optical fiber shows a higher degree of polarization than a linearly birefringent fiber when typical fiber parameter values are prescribed for the respective fibers. The theory presented here explains the experimental data well.

Asymptotic analysis of weakly guiding anisotropic optical fibers

The method of asymptotic (perturbational) power series is applied to the problem of wave propagation in a transversely anisotropic optical fiber, which has grown in importance in recent years in the process of producing a polarizationally stable monomode fiber. The dielectric waveguide structure considered in the present theory may be arbitrarily inhomogeneous and anisotropic in the transverse plane. The dielectric tensor of the guide is assumed to be only slightly different from that of the surrounding material. It is shown that the asymptotic modes are solutions to a vector differential equation of the Schrodinger type. The isotropic fiber has degenerate solutions and is, in fact, more complicated to solve. The different asymptotic dependence of the birefringence in isotropic and anisotropic guides is clearly demonstrated with the present theory. By applying variational techniques, solutions for both isotropic and anisotropic step-index and parabolic-index fibers are calculated. Emphasis is on such anisotropic guides whose solutions can be obtained from those of the isotropic fiber through a transformation.

Dispersion characteristics of inhomogeneous anisotropic optical fibers

An original numerical method is presented for the determination of mode propagation constants of inhomogeneous optically anisotropic optical fibers. The method is first checked for an isotropic step-index fiber and then applied to uniaxial anisotropic cases.

Polarization behavior in multiply perturbed single-mode fibers

A general theory is presented for polarization evolution characteristics in anisotropic single-mode optical fibers to which plural perturbations of different kinds are applied simultaneously. This treatment is based on modified coupled-mode theory. Polarization performance in the system can be described by a simple projection rule when the birefringence caused by individual perturbation is known. Several examples of applications are classified according to their mode coupling properties in fused silica fibers.