An infrared-transparent flexible glass for adaptive optics

Transparent, flexible inorganic-organic composites are essential for next-generation adaptive optics, bio-integrated sensing, and reconfigurable photonics. Despite progress in hybrid material design, achieving a material that is simultaneously flexible and transparent across a broad infrared spectrum remains a fundamental challenge. Here, we report a S₆₀Se₄₀ chalcogenide glass designed with a chain-ring dual-network architecture that overcomes this classic limitation. By integrating a dynamic covalent network of physical cross-links with heavy chalcogen elements (S, Se), this dual-network design suppresses multi-phonon absorption and ensures broadband transparency up to 21 μm, combining these optical properties with an ultralow Young's modulus (E ≈ 0.0037 GPa), extreme tensile strain (~650%), and high elastic recovery (~80%). The material further exhibits autonomous self-healing and shape-memory behavior at room temperature. We demonstrate its applicability through IR deformable lenses with tunable focal length and real-time aberration correction, showcasing capabilities in adaptive imaging and wavefront control. This work provides a versatile material platform that bridges the gap between glass-like optical performance and polymer-like mechanics, opening avenues for soft infrared photonics and reconfigurable optical systems.