Thermally reconfigurable ferroelectric nematics for spatially indexed random bit generation

Spatial optical TRNGs require entropy media with random texture generation, passive room-temperature readout, and global refreshability. Here, we demonstrate a spatially indexed TRNG based on thermally reconfigurable ferroelectric-nematic textures. Thermal reconfiguration creates random POM-readable textures that are experimentally verified to exhibit short-term temporal stability at room temperature and can be repeatedly read from predefined coordinates. Same-index scans are stable, whereas different coordinates and regenerated textures show low Pearson correlation coefficients and Hamming distances near 0.5. The median-thresholded raw stream gives a NIST SP 800-90B non-IID min-entropy rate of 0.0766 bits per raw bit, enabling SHA-256 extraction that passes NIST SP 800-22. A 6 × 6 cm² cell gives an upper min-entropy budget of ~0.11 Gbit. These results establish ferroelectric-nematic textures as addressable and globally thermally refreshable entropy media.