Optoelectronic devices using circularly polarized light (CPL) offer enhanced sensitivity and specificity for efficient data processing. There is a growing demand for CPL sensing mediums with strong optical activity, stability and sensitivity, multiple transition bands, and environmental compatibility. Here, defect-engineered chiroferromagnetic quantum dots (CFQDs) are used as a new type of CPL sensing material. By inducing amorphization defects through chiral molecules, CFQDs with high unpaired electron density, atomic structural chirality, amplified chiroptical activity, and multiple exciton transition bands are developed. CFQDs enable nonlinear, long-term plastic behavior with linear optical input, acting as in situ noise filters that reduce noise by over 20%. Additionally, CFQDs provide over nine times higher integration for photon polarization and wavelength distinctions, paving the way for next-generation processors with improved energy efficiency, integration, and reduced retention time.