Limits RegistryPUBLIC RECORD
Limits RegistryNanoporous silica aerogel-based coatings and engineered nanostructured materials have achieved refractive indices as low as about 1.025 at visible wavelengths — among the lowest indices ever achieved for a solid material — approaching the refractive index of air (1.0003) far more closely than any solid glass or plastic, and used in anti-reflective coatings and Cherenkov radiation detectors.
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Nanoporous silica aerogel-based coatings and engineered nanostructured materials have achieved refractive indices as low as about 1.025 at visible wavelengths — among the lowest indices ever achieved for a solid material — approaching the refractive index of air (1.0003) far more closely than any solid glass or plastic, and used in anti-reflective coatings and Cherenkov radiation detectors.
The lowest refractive index confirmed for a solid, self-supporting engineered material at visible wavelengths, as opposed to a gas or vacuum (n=1 by definition).
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Limits Registry. LR-LOWEST-REFRACTIVE-INDEX-SOLID-MATERIAL. Lowest refractive index of any solid material. 2026.