Optical Limiting Effect of C70 Solution at 1064 nm

In this paper, we investigate the optical limiting effect of C70 solution at a wavelength of 1064 nm. We experimentally measured the transmittance of C70 solution under three different concentrations (0.25, 0.5, and 1 mmol/L), three different solution thicknesses (5, 10, and 20 mm), and two different solvents (toluene and xylene) and obtained the values of absorption cross sections and relaxation times in the five-level absorption model of C70 solution. The influences of concentration, thickness, and solvent on the optical limiting effect of the C70 solution are analyzed. We also measured transmittance of C60 solution under the same conditions and compared the results with those of C70 solution. The experimental results show that concentration and solution thicknesses have great influence on the optical limiting ability of C70 solution. The optical limiting effect of C70 solution is better than that of C60 solution at low concentration and worse than that of C60 solution at high concentration.