Novel circularly polarized two-color quantum well infrared photodetectors based on dual dielectric column arrays

Complex environments such as underwater, haze, and backlighting require detectors with exceptional target recognition capabilities. However, neither single-polarization detection nor multi-color detection technology can fully address this challenge. Thus, integrating these two technologies emerges as a promising solution. We propose a pioneered photonic device capable of simultaneously detecting circularly polarized light and two-color signals. The device comprises a periodic array of two different GaAs pillars and a two-color quantum well infrared photodetector (QWIP). The circular dichroism of the polarized two-color QWIP reaches 0.33 at 8.5 µm and 0.26 at 10.5 µm. This design bridges the gap in simultaneous polarized and multi-color signal detection, potentially pioneering a new generation of infrared detectors.