UV laser-induced poling inhibition in lithium niobate crystals

The development of methods for ferroelectric domain engineering in lithium niobate (LN) is of special importance as it not only enables the fabrication of efficient non-linear devices (PPLN) but also constitutes a very effective path towards micro-structuring of this important ferroelectric crystal. UV laser-induced poling inhibition is a process whereby domain inversion is prohibited as a result of previous UV laser irradiation of the crystal. The effect was first demonstrated using a frequency-doubled argon ion laser (244 nm) to irradiate the +z face of congruently melting undoped and MgO-doped LN single crystals followed by electric field poling. In that initial report the potential of the method for both, ferroelectric domain engineering and micro-structuring, was demonstrated.