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Paraxial light beams in structured anisotropic media

Research output: Contribution to journalArticleScientificpeer-review


Original languageEnglish
Pages (from-to)2019-2024
Number of pages6
JournalJournal of the Optical Society of America A: Optics and Image Science, and Vision
Issue number11
Publication statusPublished - 1 Nov 2017
Publication typeA1 Journal article-refereed


We discuss the paraxial approximation for optical waves propagating in a uniaxial anisotropic medium inhomogeneously twisted on the plane normal to the wave vector, with the latter being parallel to one of the two principal axes normal to the optic axis. Such geometry implies a continuous power transfer between the ordinary and extraordinary components, regardless of the input beam polarization. We pinpoint that this peculiar feature, generalizable to any inhomogeneous linear birefringent material, strongly affects the application of the paraxial approximation due to the simultaneous presence of two different phase velocities. We eventually show that a local coordinate transformation permits a correct application of the paraxial approximation.