Unprecedented Silver‐Based Hybrid Pyroelectric Enabling Wide Spectral Photo‐Pyroelectricity for Birefringence Photomodulation

Birefringent crystal, which has the capacity to manipulate polarization light, holds an indispensable position in optics and optoelectronics, while it remains challenging to fulfill the modulation of birefringence. Here, we present wide spectral photo-pyroelectric effect in a silver-based hybrid pyroelectric, (N-CHM)Ag₂I₃ (N-CHM=N-cyclohexylmethylamine), serving as a feasible strategy to regulate birefringence through light stimuli. As the first silver-based hybrid pyroelectric, (N-CHM)Ag₂I₃ exhibits strong room-temperature photo-pyroelectricity with a large polarization of ~3.23 μC/cm² and high voltage responsivity of ~0.96 m²/C across the UV-NIR spectral region. Strikingly, the photomodulation of its in-plane birefringence is established through pyroelectric effect, giving a saturation value of ~1.68×10^-2 that is among the highest level achieved to date. This study on the birefringence photomodulation of lead-free hybrid pyroelectric is anticipated to boost future development of new smart optical and optoelectronic devices.