Pyroelectric effect in green light-assisted domain reversal of Mg-doped LiNbO_3 crystals

We developed a real-time imaging system to probe the light-assisted domain reversal process of Mg-doped LiNbO(3). An interesting phenomenon was observed where the domain appeared to reverse just after the laser was obscured. An exclusive electric field of about 350 V/mm was measured at 532 nm of light irradiation at an intensity of 6.6 × 10(4) W/cm(2). The exclusive electric field was considered to be produced by a pyroelectric effect owing to a temperature change in the region of irradiation. The temperature change in the light-irradiated region was calculated to be about 2.3°C. Our experimental results indicate that a change of the electric field caused by the pyroelectric effect may play a significant role when LiNbO(3) or other ferroelectric crystals are used under strong light.