Circularly Polarized Light Photodetector Based on X-Shaped Chiral Metamaterial

We propose a new type of circularly polarized photodetector based on double-layer chiral planar metamaterial in the form of X shape. The metamaterial, realizing a high circular dichroism at 550-nm wavelength, is fabricated on a reverse-biased p-i-n diode. The light incident on the device, is filtered by the metamaterial, and then absorbed by the p-i-n diode, forming photocurrent. Our demonstrated circularly polarized photodetector have a strong ability to distinguish between left- and right-hand circularly polarized light and will be very promising for practical applications in optical communication of spin information, quantum-based optical computing, and circular dichroism spectroscopy.