Polarization and propagation characteristics of switchable first-order azimuthally asymmetric beam generated in dual-mode fiber.

摘要: We report here the controlled generation of a linearly polarized first-order azimuthally asymmetric beam (F-AAB) in dual-mode fiber (DMF) by appropriate superposition selectively excited zeroth-order vector modes that are doughnut-shaped symmetric beams (D-ASBs). first demonstrate continually switching polarization mode structures having an identical two-lobe intensity profile (i.e., intra-F-AAB conversion). Then, under distinct launching state, we generate progressively toggling between and pattern dissimilar orientations F-AAB to D-ASB Interestingly, decentralized elliptical Gaussian possessing homogenous spatial is obtained enhancing contribution fundamental (HE11/LP01) F-AAB. A smoothly varying azimuth input this situation resulted redistribution transverse energy procuring unique exciting unconventional two-grain T-polarized mutually orthogonal state (SOP). All above three were achieved given set conditions (tilt/offset) (TEM00) devised with changing SOP beam. strong modulation output characteristics was also observed variation propagation distance (for fixed SOP) owing large difference constants participating (LP01 one F-AABs). Finally, particular study led design for low-cost highly sensitive strain measuring device based on tracking centroid movement pattern. Each our experimentally intensity/polarization distributions theoretically mapped one-to-one basis considering linear appropriately LP waveguide toward complete understanding structure.