Highly efficient generation of second and third harmonics of a femtosecond Cr:forsterite laser in nonlinear optical crystals

Highly efficient generation of the second (η_2ω=69%) and third (η_3ω=26%) harmonics of a femtosecond Cr:forsterite laser radiation is achieved. It is shown that for the pump intensity exceeding 50 GW cm^-2 (η_2ω=60%), the third-order nonlinearity begins to play a significant role, resulting in a deterioration of the spectral parameters of the generated harmonics.