Studies of third-order optical nonlinearities and optical limiting of 2, 3-butanedione dihydrazone

2, 3-butanedione dihydrazone (BDDH) synthesized via chemical route and nonlinear optical parameters, such as nonlinear refractive index (n2), nonlinear absorption coefficient (β), third-order nonlinear optical susceptibility (χ(3)), second hyperpolarizability (γ), and optical-limiting behavior were investigated by single beam z-scan technique for different concentrations. Synthesized sample were irradiated by a Q-switched, frequency doubled Nd:YAG laser and found that n2 and β increases linearly with increasing concentration and hence γ decreases linearly. The excited-state absorption cross sections of BDDH were found to be larger than ground-state absorption cross sections, and it leads to reverse saturable absorption (RSA). The experimental results are well in agreement with the theory and also establish BDDH as one of the potential candidate materials for optical limiting at 532 nm.