Controllable Chiral Lattices for 2D ROA Mapping and a Long-term Stable Broadband CPL Detector

Abstract Circularly polarized light (CPL)-sensitive detector enables various techniques such as quantum computing, spin optical communications, and magnetic recording. However, limited responsive wavelength range and low stability of the common CPL detecting materials have hindered explosive applications of CPL detectors. Here, we introduce atomic chiral Se nanorods films as a broadband CPL detector, taking advantage of the intrinsic atomic chirality and the stability of inorganic Se nanocrystals. An incident circular polarization (ICP)-Raman optical activity (ROA) mapping technique is also performed to examine the chiroptical activity of the large-area CPL detecting films. This ROA mapping technique is firstly presented with our knowledge as a new analytic method for chirality of 2D materials. The monolayered Se NRs detect circularly polarized light in broad wavelengths from UV to SWIR with the responsivity dissymmetry factor (gres) up to 0.4 with high stability at ambient conditions for longer than 1 year. The CPL-sensitive Se NRs will also be employed in various applications, such as chiral photonic synapses, chiral spin devices, and CPL-sensitive photocatalysts. Furthermore, our ICP-ROA mapping technique will open a new door to the development and analysis of 2D chiral materials.