Abstract
Detecting circularly polarized light (CPL) plays a crucial role in emerging technologies such as advanced display systems, autonomous sensing, secure optical communication, and quantum information processing. However, current CPL detectors often require bulky optical components and have limited spectral ranges, limiting integration and sensitivity. In this study, we present a flexible broad-spectrum CPL sensor by integrating with a SnSe thin film onto a chiral nematic cellulose nanocrystal (CNC) film substrate. The CNC film has a tunable helical pitch that selectively reflects CPL in the visible to near-infrared range via Bragg reflection, enabling direct discrimination of polarization handedness. Our device exhibits clear photocurrent responses across both visible and near-infrared wavelengths with distinct sensitivity to the handedness of CPL. This approach provides the development of chiral photodetectors, enabling compact, high-performance, and flexible CPL detection systems for next-generation optoelectronic applications.