Magnetically tuned absorptive optical nonlinearity in NiO thin films

Effect of magnetic field on the absorptive optical nonlinearity in ion beam sputtered as-deposited and annealed NiO thin films have been studied and the magnetic field dependent nonlinear absorption coefficients are obtained. As-deposited NiO thin film is more sensitive to magnetic field due to higher percentage of oxygen vacancies and shows gradual variation as well as sign reversal of nonlinear absorption coefficients with increase in applied magnetic field. In annealed film, we found increase in nonlinear absorption coefficient with increasing magnetic field.