Bulk single crystals of ammonium acid phthalate grown by the Sankaranarayanan–Ramasamy method for optical limiting applications

Transparent ammonium acid phthalate (AAP) crystal of length 55mm and diameter 18mm has been grown from aqueous solution along using the Sankaranarayanan–Ramasamy method. The unit cell parameters were confirmed by single crystal X-ray diffraction analysis and it belongs to orthorhombic system. The crystalline perfection of grown crystals was analyzed by high-resolution X-ray diffraction. The UV–vis–NIR spectrum showed that the grown crystal is transparent in the entire visible region. Nonlinear optical absorption of the sample has been studied at 532nm using single 7ns laser pulses, employing the open-aperture Z-scan technique. It is found that the AAP crystal is a potential candidate for optical limiting applications. The laser damage threshold was measured using Q-switched Nd:YAG laser (1064nm). •Bulk growth of ammonium acid phthalate has been achieved.•High crystalline perfection and laser damage threshold have been achieved.•High transparency is observed in unidirectional crystal compared to conventional crystal.•Two photon absorption co-efficient was calculated by Z-scan technique.