Schlieren and interferometric investigations of laser breakdown in liquids

Shadow and interference methods were used in qualitative and quantitative investigations of the processes occurring in acetone, benzene, water, glycerin, nitrobenzene, carbon tetrachloride, toluene, formamide, and ethanol (of standard purity) as a result of focusing of giant ruby laser pulses of up to 200 kW power. The changes in the refractive index Δn at the threshold breakdown power were determined. Allowance for the nonlinearity of the absorption coefficient was necessary in an analysis of the formation of breakdown filaments.