Potassium titanyl arsenate crystals (KTA) exhibit large non-linear optical and electro-optical coefficients in contrast to KTP and also have a lower absorption in the range of 2.0µm-5.0µm. The large non-linear coefficients are associated with large angular and temperature ranges. Another advantage of arsenates are low dielectric constants, low loss tangents and lower ionic conductivities, which are orders of magnitude lower than for KTP. The single crystals of these arsenates are chemically and thermally stable, non-hygroscopic and highly resistant to high laser intensities.

KTA is used for second harmonic generation (SHG), sum frequency generation (SFG), difference frequency generation (DFG), optical parametric oscillator (OPO), electro-optical Q-switch and modulator as well as a substrate for optical waveguides. OPOs based on KTA crystals are reliable sources for tunable lasers with energy conversion efficiencies of over 50%.

KTA has a very high damage threshold. No optical damage has been observed at energies of ^10GW/cm2 – ^20GW/cm2 with ps dye lasers. This crystal is grown using a high temperature flow technique.