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doped samples in comparison to the pure KDP sample and decrease with
increase in doping level. The variation of a.c. resistivity with applied frequency is
also presented. The low dielectric loss values in doped crystals have indicated
that the doping do not introduce major defects in the crystals. The lowering of
dielectric constant values due to doping makes the crystals good candidates for
electro-optic applications, which needs lower dielectric constants.
Chapter VI describes the nonlinear optical properties of grown pure and amino
acids doped KDP crystals and UV-Vis measurements. The Kurtz and Perry
powder method has been used to determine the second harmonic generation of
laser beam. A Q-switched, mode locked Nd:YAG laser of 6 mJ/pulse at 1064 nm
fundamental radiation is passed through the powdered samples filled in a fine
capillary and the radiation emitted by the samples is detected by photodiode
detector. The second harmonic radiation intensity is compared with the standard
KDP sample. Thus the figure of merit of the SHG for the sample is estimated. It
has been found that as the doping of amino acids increases in KDP crystals the
SHG efficiency increases. It is beneficial to add amino acids in KDP crystals. The
UV-Vis spectra of pure and doped KDP crystals suggest that the optical
transmission increases on doping of amino acid. The UV- cut off limit slightly
decreases on doping; however, in case of L-threonine doping it remains
unaltered. The slight loss of UV cut off limit is the disadvantage of doping, but L-
threonine doping is the better option.