The invention relates to a
large size potassium strontium borate
nonlinear optical crystal, the preparation and use thereof. The formula of the
crystal is: KSr4B3O9, which belongs to rhombic
system, the
space group is Pna2(1), and the molecular weight is 566.01, and the
crystal size is 10-60mmx10-60mmx10-60mm. The preparation contains the following steps of: evenly mixing the
potassium strontium borate compound with a fusing assistant, heating, maintaining the constant temperature, cooling to the saturation temperature and obtaining a mixture solution, placing a
seed crystal into the mixture solution, lowering the temperature to the saturation temperature to obtain the required crystal, and subsequently extracting the crystal from the liquid level, cooling to
room temperature, and finally obtaining the
large size potassium strontium borate
nonlinear optical crystal. The
nonlinear optical effect of the crystal is approximately the same as the KDP, the transparent optical band is 220nm-3000nm. The crystal is simple in operation, low in cost, large in crystal size, short in growth period, less in
coating, high in laster damage threshold, good in
mechanical property, firm, stable in physicochemical properties, uneasy to deliquescence, convenient for
processing and storage, or the like. Accordingly, the
nonlinear optical crystal of the invention can be abroadly applied in nonlinear optical devices such as frequency doubler,
optical parametric oscillator or the like.