Periodically poled KTiOAsO4 crystals for optical parametric oscillation

Polarization switching and dielectric spectroscopy of KTiOAsO4 (KTA) crystals have been studied. This has allowed, for the first time, the fabrication by low temperature poling of periodically-poled domain structures in KTA crystals (0.5 mm thick, 10 mm long) and also the observation of optical parametric oscillation in the mid-infrared region. The integrity of the periodic domain pattern and the structural perfection of the periodically poled crystal have been demonstrated using scanning electron microscopy (SEM) and high-resolution x-ray diffraction imaging.