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Birefringence enhancement by using D-shaped microstructured optical fibers

In this study, a detailed numerical investigation is presented, seeking to enhance the birefringence effect by using D-shaped microstructured optical fibers (MOFs). We studied a D-shape core geometry associated with three different air-hole configurations: circular and elliptical, aligned with either the x-direction or the y-direction. Results have shown that ultrahigh birefringence MOFs, with B values of the order of 10−2 for a wide range of wavelengths, can be obtained. The highest birefringence B was equal 3.97 × 10−2, a value found for a D-MOF (circular holes) at 1550 nm. To the best of our knowledge, this is the highest theoretical value in the published literature.