Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published April 15, 2015 | public
Journal Article

Q-plates as higher order polarization controllers for orbital angular momentum modes of fiber

Abstract

We demonstrate that a |q|=1/2 plate, in conjunction with appropriate polarization optics, can selectively and switchably excite all linear combinations of the first radial mode order |l|=1 orbital angular momentum (OAM) fiber modes. This enables full mapping of free-space polarization states onto fiber vector modes, including the radially (TM) and azimuthally polarized (TE) modes. The setup requires few optical components and can yield mode purities as high as ∼30  dB. Additionally, just as a conventional fiber polarization controller creates arbitrary elliptical polarization states to counteract fiber birefringence and yield desired polarizations at the output of a single-mode fiber, q-plates disentangle degenerate state mixing effects between fiber OAM states to yield pure states, even after long-length fiber propagation. We thus demonstrate the ability to switch dynamically, potentially at ∼GHz rates, between OAM modes, or create desired linear combinations of them. We envision applications in fiber-based lasers employing vector or OAM mode outputs, as well as communications networking schemes exploiting spatial modes for higher dimensional encoding.

Additional Information

© 2015 Optical Society of America. Received February 3, 2015; accepted March 2, 2015; posted March 13, 2015 (Doc. ID 232541); published April 8, 2015. The authors would like to thank P. Kristensen for help with fiber fabrication. This work was funded in part by the DARPA InPho program under grant nos. W911NF-12-1-0323 and W911NF-13-1-0103, and NSF grant no. ECCS-1310493. P.G. acknowledges support from NSF-GRP grant no. DGE-1247312. E. K. and R. B. would like to acknowledge the support of the Canada Excellence Research Chairs (CERC) program.

Additional details

Created:
August 20, 2023
Modified:
October 20, 2023