Modulational instability and formation of a nonlinear oscillatory structure in a " focusing " medium
نویسنده
چکیده
is well known as the universal model for the description of the unstable envelope of strongly dispersive and weakly nonlinear waves. The other interpretation of ( 1 ) is connected with the nonlinear optics of the focusing media (see, e.9., refs. [ 1-3] ). The field of the important physical applications of the NLS equation is extromely wide. To mention just a few: nonlinear deep water waves [4 ], Langmuir waves in plasma [ 5 ], and nonlinear propagation of plane dif: fractive wave beams in the focusing regions of the ionosphere [6 J. By means of the change of variables,
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تاریخ انتشار 1993