Fig. 1. Schematic and phase distribution of the spin-dependent grating for LCP light. (a) Schematic of the spin-dependent grating. (b) Calculated phase distribution of the spin-dependent grating along with two magnified pictures of the liquid crystal molecule distributions and their phase distributions. (c) Phase distribution of the spin-dependent grating under a polarizing microscope.

Fig. 2. (a) Setup for device characterization by measuring the arbitrary polarization states of light. (b) Experimental results for 72 sets of Stokes parameter measurements. PC, polarization controller; HWP, half-wave plate; QWP, quarter-wave plate; POL, polarizer; PD, photodetector.

Fig. 3. High-speed Stokes optical communication system. PMF, polarization-maintaining fiber; DP-IQ modulator, dual-polarization in-phase/quadrature modulator; AWG, arbitrary waveform generator; SMF, single-mode fiber; PC, polarization controller; EDFA, erbium-doped fiber amplifier; OTF, optical tunable filter; VOA, variable optical attenuator; POL, polarizer; Col, collimator; PD, photodetector.

Fig. 4. Normalized polarizations of the 16QAM signals in the Stokes space.

Fig. 5. Stokes communication when using the spin-dependent grating as a receiver. (a) Plots of retrieved Stokes vectors on the Poincaré sphere for 32 GBd QPSK, 16 GBd 8PSK, and 16 GBd 16QAM signals. (b) Corresponding constellation diagrams for the vectors in (a). (c) Bit error rate (BER) curves of the 32 GBd QPSK, 16 GBd 8PSK, and 16 GBd 16QAM signals with received power. (d) BER curves of the 32 GBd QPSK, 16 GBd 8PSK, and 16 GBd 16QAM signals with different wavelengths.