X-ray-induced phase transformation in congruent and vapor-transport-equilibrated lithium tantalate and lithium niobate

We have discovered an effect of a partially reversible x-ray-induced increase of diffuse x-ray scattering in both congruent and vapor-transport equilibrated single-crystalline lithium niobate and lithium tantalate. The effect has been attributed to x-ray-induced decay of the ferroelectric phase at room temperature. The x-ray-induced change of the switching current and hysteresis loops observed is in accord with this assumption.