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Register a new userThird and fifth harmonics generation by tightly focused femtosecond pulses at 2.2 {mu}m wavelength in air
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We report experiments on the generation of third and fifth harmonics of millijoule-level, tightly focused, femtosecond laser pulses at 2.2 {mu}m wavelength in air. The measured ratio of yields of the third and fifth harmonics in our setup is about 2 cdot 10-4. This result contradicts the recent suggestion that the Kerr effect in air saturates and changes sign in ultra-intense optical fields.
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