Fig. 5. Experimental measurements of the phase reconstruction, phase purity, and scattering efficiency for the generation of polarization diversity OAM modes.

(A) Measured far-field intensity profiles, collinear interferograms, tilt interferograms, and reconstructed phase structures of the generated y-pol. OAM₊₁ at 1500, 1550, 1600, and 1630 nm. (B) Measured phase purity of the generated y-pol. OAM₊₁ versus wavelength (1500 to 1630 nm). (C) Measured phase purity of the generated y-pol. OAM₊₁ versus length l of the grating region with two depths of 100 and 120 nm. (D) Measured scattering efficiency of the generated y-pol. OAM₊₁ versus wavelength with two depths of 100 and 120 nm.