Photothermal poling of nonlinear optical polymer films

Photothermal heating of a nonlinear optical polymer film with a focused laser beam leads to local temperatures above the glass transition so that the molecular dipoles orient in the electric field applied to the electrodes. Periodic switching of the field direction during movement of the sample yields gratings with alternating polarity which were studied with scanning electro-optical microscopy. The width and the depth of the poled stripes were probed with electro-optical and pyroelectrical techniques, respectively. Photothermal poling may be combined with other poling techniques in order to produce various dipole-orientation patterns for device applications.