Chiral materials present transformative opportunities for controlling photon polarization through inherently asymmetric light–matter interactions. A central challenge lies in achieving efficient symmetrical breaking in nanostructures to enable scalable, high-performance circular polarization modulation. Among various approaches such as top-down lithographic patterning to chiral ligand–directed lattice growth, the self-assembly of colloidal nanoparticles offers a simple, versatile and scalable route to hierarchically structured chiral architectures with strong electromagnetic coupling at optical wavelength ranges. These systems not only maximize anisotropic light–matter responses but also enable dynamic control of polarization-resolved absorptions, transmission and emissions. However, practical deployment demands overcoming challenges such as thermal and photonic stability, preservation of polarization fidelity under extreme environmental conditions, and real-time metrology for chiral photon generation across photoluminescence, electroluminescence, and thermoradiative regimes. Addressing these gaps will unlock new pathways in quantum photonics, advanced sensing, and next-generation optical communication technologies.
