Femtosecond nonlinear optical refraction of single crystal alumina doped with copper ions

Abstract

The single crystal alumina was fabricated by the Czochralski method. The copper ions were doped into the alumina sample to form the Cu:Al2O3 composite material. The doping energy is 35keV and the ion concentration is 1.2×1017 ions/cm2. The suppercontinuum spectrum was investigated to show the larger nonlinear refraction of this composite material. The nonlinear optical refractive property of the Cu:Al2O3 composite material was investigated by using the Kerr-lens autocorrelation technique for the first time. The nonlinear optical refractive indices, n2=2.8×10−15cm2/W at 800nm, is larger than the value of the single crystal alumina. The mechanism of the nonlinear optical refraction has been discussed and it is due to the optical Kerr effect.