Prof. Oz M Gazit
28.3.2024
אודיטוריום ע"ש דויד וואנג, בניין מידן, קומה 3
14:30
Numerous bio-organisms employ template-assisted crystallization of molecular solids to yield crystal morphologies with unique optical properties that are difficult to reproduce synthetically. We developed a facile procedure to deposit bio-inspired birefringent crystals of theophylline on a template of single-crystal quartz. Crystalline sheets with well-defined orientation were obtained, giving rise to high optical anisotropy in the plane parallel to the quartz surface, with a refractive index difference of Δn ≈ 0.25 and a refractive index along the slow axis of n ≈ 1.7. A classical crystallization mechanism was observed by time-resolved AFM. Finally, patterning of the crystalline stripes with a tailored periodic grating leads to a thin organic polarization-dependent diffractive meta-surface, opening the door to the fabrication of various optical devices from a platform of small-molecule-based organic dielectric crystals.