Am. Kamchatnov et F. Ginovart, PERIODIC-WAVES AND SOLITONS OF 2-PHOTON PROPAGATION, Journal of physics. A, mathematical and general, 29(14), 1996, pp. 4127-4139
We study the two-photon propagation (TPP) modelling equations. The one
-phase periodic solutions are obtained in an effective form. Their mod
ulation is investigated by means of the Whitham method. The theory dev
eloped is applied to the problem of creation of TPP solitons on the sh
arp front of a long pulse.