Zinc potassium phosphate hexahydrate crystals for nonlinear optics

Zinc potassium phosphate hexahydrate (ZnKPO4.6H2O) (abbreviated as ZPPH) single crystal is grown by reacting Potassium dihydrogen phosphate with Zinc Sulphate in equimolar ratio by slow evaporation. This compound crystallizes in the acentric orthorhombic symmetry class (space group Pmn21) and possesses photo induced optical second harmonic generation. The laser induced surface damage threshold for the grown crystal was measured as 1.7 × 1012 mJ/cm2 with Nd:YAG laser assembly which is of the same order as that of the reference KDP used in our experiment. The temperature dependent second harmonic generation studies were also carried out from room temperature to liquid helium temperature and the anomalies at low temperature qualifies this material as efficient low temperature optical switchers