Adding/dropping polarization multiplexed cylindrical vector beams with local polarization-matched plasmonic metasurface

Abstract

Here we propose a polarization-dependent gradient phase modulation strategy and fabricate a local polarization-matched metasurface to add/drop polarization multiplexed cylindrical vector beams (CVBs). The two orthogonal linear polarization states in CVB multiplexing will represent as radial- and azimuthal-polarized CVBs, which means that we must introduce independent wave vectors to them for adding/dropping the polarization channels. By designing the rotation angle and geometric sizes of a meta-atom, a local polarization-matched propagation phase plasmonic metasurface is constructed, and the polarization-dependent gradient phases were loaded to perform this operation. As a proof of concept, the polarization multiplexed CVBs, carrying 150-Gbit/s quadrature phase shift keying signals, are successfully added and dropped, and the bit error rates approach 1 × 10−6. In addition to representing a route for adding/dropping polarization multiplexed CVBs, other functional phase modulation of arbitrary orthogonal linear polarization bases is expected, which might find potential applications in polarization encryption imaging, spatial polarization shaping, etc.

Vector Beam Generation from Standing Hollow GaN Nanowire Lasers on Sapphire Substrates

“…A simple method is mode manipulation by stressing optical fiber from the outside, , but it suffers from mode controlling difficulties and optical loss. Even when a ring resonator, , a plasmonic metasurface, , or a hologram , is used, it is a passive element and requires an external light source. Of the methods that use active devices, a simple one is to create point defects in a Fabry–Perot cavity. , This method is very inefficient because it introduces loss in the cavity, and the device itself may be bulky, which increases its operation energy.…”

Optical vectorial-mode parity Hall effect: a case study with cylindrical vector beams

“…By adjusting dimensions of the meta-atoms, vectorial manipulation is achieved through locally effective birefringence 16 , 17 , thereby modifying the local SOP of the impinging waveform. This form-birefringence-based metasurface has found wide applications in meta-lenses 18 – 21 , structured light field manipulation 22 – 24 , and holography 25 – 28 , providing a promising platform for manipulating VOFs at the nanoscale. One notable characteristic of VOFs is their presence of a pair of degenerate modes with different polarization mode parities.…”