Effect of Magnesium Doping on Second-Order Nonlinear Optical Behavior of Lithium Niobate Crystal: A Theoretical Approach
Namita Sisodia, K.S. Bartwal and Pratima Sen
Effect of Magnesium doping on the second-order nonlinear optical behavior of lithium niobate crystal has been theoretically studied. The contribution of bound charge carriers and free charge carriers have been considered to determine the second-order susceptibility of the medium. Semi classical density matrix approach is used to consider the effect of bound charge carriers where as the free charge carriers are taken into account by using the hydrodynamic model of free electronic gas. The results show that the nonlinear optical response of Mg doped lithium niobate crystal at 1064 nm decreases linearly with increasing doping concentration. At threshold doping concentration i.e 5 mol % of Mg doping concentration it is minimum and beyond this doping concentration it again increases. The second harmonic intensity of Mg doped LN crystals due to free charge carriers and bound charge carriers as a function of pump requency has also been plotted.
Keywords: Nonllinear material, nonliner optics, optical susceptibility, self focusing and defocusing
PACS Numbers: 42.70.Nq, 42.70.Np, 42.65.-k, 42.65.An, 42.65.Jx