Fig. 5: The performance of the endless automatic polarization controlling device.
From: High-performance polarization management devices based on thin-film lithium niobate
a The schematics of the proposed endless automatic polarization controlling device. DAC digital-to-analog converter, ADC analog-to-digital converter, FPGA field-programmable gate array, PD flip-chip bonded photodetector. b The microscope image of the fabricated device. θ1, θ2, θ3 and θ4 in a and b mark the phase shifters. c The normalized optical power of the PD as a function of the rotation angle of the input polarization. Insets: the rotation trajectories of the input polarization states for demonstrating the capability of the endless operation. d The normalized optical power of the feedback signal as a function of the polarization scrambling rate
