Photoinduced Motions at the Macroscopic Level

We discovered this phenomenon by chance when attempting to compare the efficiency of the photoinduced birefringence process with the efficiency of the refractive index modulation under electric field in photorefractive polymers. 

15 Hexagonal surface relief panem written on a chin film. 

16 Schematic representation of the mechanism of surface gratipgs fcNTnation, involving pressure gradients. P is the pressure, I represents the light intensit) and isomerization, and x is the place on the polymer film. 

Research in the area of photoinduced surface-relief gratings is extremely active. One review covers the literature published until 1998, but the field has practically exploded. One recent paper even reports the creation of a holographic grating with a single short laser pulse, although there are reports questioning the mechanism.  

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