Full-stokes polarization photodetector based on the chiral metasurface with the dislocated double gold rod configurations

Abstract

The filterless polarization-sensitive optoelectronic device generally has low discrimination, thus severely hindering the development of monolithic full-polarization detectors. We numerically demonstrate a circular polarization photodetector composed of the dislocated 2-bar gold chiral metasurfaces modulating the circular polarization lights and the InGaAs/InP detector chip detecting light intensity signals. The chiral metasurfaces excite the electric field loops with different spins when irradiated with different chiral light, and it explains the high extinction ratios of 21:1 in circularly polarized detectors. In addition, the linear dichroism (LD) and extinction ratios (ER) of the linear polarization device are 0.85 and 80:1, respectively. The excellent ER performance is caused by the boundary state between the metal grating and the InP substrate. The full Stokes pixel based on the six-image-element technique can almost accurately measure arbitrary polarized light at 1550 nm operation wavelength, whose errors of the degree of linear polarizations (Dolp) and the degree of circular polarizations (Docp) are less than −35 dB and −10 dB, respectively.