On harmonic generation in a photoionized gas

The laws characterizing the radiation of high harmonics due to the coherent bremsstrahlung effect are indicated in the limit of high intensity of the laser pump photoionizing a gas in regime of suppression of the ionization barrier. It is shown that the intensity of the harmonics is determined by the quantum properties of the electron distribution in an atom before it is ionized. Pis’ma Zh. éksp. Teor. Fiz. 69, No. 7, 486–490 (10 April 1999)