Publication: Three-dimensional analysis of bending losses in dielectric optical waveguides with arbitrary refractive-index profile
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Optical Society of America
A three-dimensional analysis of bending losses in dielectric optical waveguides is presented. It constitutes a nontrivial generalization of previous two- and three-dimensional studies by other authors. Our analysis is based on homogeneous integral equations for the total radiation field and suitable asymptotic approximations for Green’s functions. A key role is played by a new three-dimensional approximation for a relevant Bessel function with large order and argument (the former being larger than the latter). A nontrivial check of the consistency of all those approximations is given. General formulas are presented for the radiated field and the energy flow and for a bending-loss coefficient in three dimensions. Numerical results are also given, in order to assess the difference between the results of other authors and ours. Such a difference is rather small for monomode behavior near cutoff, increases as the behavior of the waveguide changes from monomode to multimode, and decreases as the parameter V increases for a given core radius and propagation mode.
© 1987 Optical Society of America. M. L. Calvo acknowledges the partial financial support received from the Spain-USA Joint Committee for Scientific and Technical Cooperation and is grateful to Jay M. Enoch for his kind hospitality at the School of Optometry, University of California at Berkeley. R. F. Alvarez-Estrada acknowledges the partial financial support received from the Council for International Exchange of Scholars through a Fulbright-MEC Fellowship and is grateful to B. Zumino for his kind hospitality at the Theoretical Physics Group, Lawrence Berkeley Laboratory.
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