Abstract

Potassium dihydrogen phosphate (KDP) crystals are used widely as frequency multipliers and optical switches for high power lasers and must have high damage thresholds. Typical as-grown crystals had a bulk laser damage threshold of 6-9J/cm² against 1ns pulse at 1μm laser wavelength¹⁾. KDP crystals are usually grown from aqueous solutions in the temperature range between 60-20°C. We discovered the increasing of microbes in the KDP solution during the growth term. If these microbes or their carcasses are incorporated into the growing crystals, the damage threshold will show values lower than the intrinsic value because the damage threshold of the organic material is much lower than that of the inorganic materials.

© 1988 Optical Society of America