Fast lateral photovoltaic effect in ferroelectric LiNbO_3 single crystals

We report the fast lateral photovoltaic effect in pure congruent LiNbO3 crystal induced by pulsed laser and continuous wave laser with wavelengths of 355,532,and 1064 nm.A typical ultrafast photovoltage can be observed on the surface perpendicular to the c axis,with the rise time of 1.5 ns and the full-width at half-maximum of 1-2 ns,when the laser pulse inhomogeneously irradiates on the crystal.The peak open-circuit photovoltages show a linear dependence on the incident laser intensities.The mechanism of t...