Impact of aluminum doping on nonlinear absorption and ultrafast carriers dynamics of Al:CdO thin films

•Al:CdO thin films with different doping concentrations were designed and synthesized.•The structure and properties of the film were studied.•The change of Al concentration can effectively modulate the nonlinear optical properties of Al:CdO films, and the maximum nonlinear absorption coefficient is 2 × 10−6 m/W.•The results of the study on the carrier dynamics characteristics of the films show that the relaxation lifetime of the carriers, the absorption cross-section of the carriers and the refraction volume of the carriers in the high-aluminum-concentration films are all increased.