Optical frequency doubling in microtube Czochralski (μT-CZ) grown benzophenone single crystals

Microtube Czochralski pulling technique (μT-CZ) is a novel method of growing bulk organic single crystals using microtube as a seed. This technique was successfully utilized for the bulk growth of benzophenone single crystals, which is a potential organic non-linear optical material. The important growth parameters were optimized for the present system. The optimized growth parameters are as follows: pulling rate, 1-2 mm/h; seed rotation rate, 10 rpm; and the axial thermal gradient, 8 °C/cm. X-ray rocking curve studies on the cut and polished wafers made out of the grown crystals confirm better crystalline quality. Fourier transform infrared spectroscopy was performed to ascertain the functional groups and UV-VIS-NIR spectroscopy was carried out to evaluate the optical quality of the grown sample. Powder second harmonic generation (SHG) measurement shows that the grown samples exhibit nearly three times higher SHG than potassium dihydrogen phosphate (KDP).