Large-Area Three-Dimensional Displaced Overlapping Wing Perovskite Metamaterials with Giant Optical Chirality

Perovskite chiral metamaterials have attracted widespread attention due to their enormous potential in areas such as chiral photoelectronics, spintronics, and ferroelectricity. However, current research often struggles to balance large-area fabrication with strong optical chirality responses. Here, we design and fabricate a novel three-dimensional displaced overlapping structure. A universal method combining electrochemical templating and stepwise glancing angle deposition enables large-area sample fabrication (1.4 cm × 1.4 cm). Ellipsometry-based circular dichroism measurements reveal a strong chiroptical response with a CD value of 12,149 mdeg and an anisotropy factor of 0.82 at 700 nm. Simulations indicate that the response originates from the resonant coupling of parallel electric and magnetic dipole components within the structure, with extrinsic chirality tunable via the incident light angle. Compared to conventional nanofabrication, this approach increases the production area by 4 orders of magnitude while offering tunable polarization conversion (1° to 32.6°). This work provides a viable pathway for developing large-area, low-cost polarizers, imaging, displays, and biosensors.