Abstract-In this article a new type of circularly cored highly birefringent (Hi-Bi) waveguide having elliptical cladding is proposed and analyzed for the first time in our knowledge. By choosing appropriate orthogonal co-ordinates and using the boundary conditions of the considered waveguide, the eigen value equation in terms of modified Mathieu functions is derived under the weak guidance condition and is presented in this paper. Using this equation the modal dispersion curves for even and odd guided modes are obtained and plotted for different cladding ellipticity e. It is seen that the proposed (Hi-Bi) fiber supports less guided modes than standard circular fiber. Finally, the modal birefringence in the said fiber is also estimated.

have shown that the performance of the meander line is superior to the ESB structure in a wide range of frequencies.The frequency-selective properties of ESB structures may be exploited to build band-stop filters. However, the performance of such filters does not follow any standard characteristic (e.g., Chebyshev or elliptic). Hence, the ESB structures are inferior to classical printed-circuit filters.

By using the method of separation of variables in the elliptical coordinate system, a representative formula in terms of Mathieu and modified Mathieu functions is derived and longitudinal field components for the even and odd modes are presented for the proposed fiber. The eigen value equation for the fiber to be considered is obtained by solving the fourth order determinantal equation under weak guidance condition and is given in this paper. The cutoff frequency of several lower orders modes for different eccentricities have been obtained and their propagation characteristics have been plotted. The effect of the eccentricity on the modal cutoff values and mode transmissions is discussed. Finally, the modal birefringence in the proposed fiber is also estimated.

No abstract

We present the modal analysis and dispersion curves of some asymmetric annular optical-fiber waveguides. The proposed cross-sections can be conceived as having the shape of a distorted annular circular waveguide and leads to a tolerance study of deformation in an annular optical-fiber waveguide. We obtain mathematical expressions for the modes of the proposed waveguides using boundary matching techniques under some logical assumptions. We observe that the proposed distortions are able to tune the cutoff values of annular circular waveguide at desired levels.