Abstract:
We consider a system of equations describing stimulated combination
scattering of light. We show that solutions of this system are expressed
in terms of two solutions of the sine-Gordon equation that are related to
each other by a Bäcklund transformation. We also show that this system is
integrable and admits a Zakharov–Shabat pair. In the general case,
the system of equations for the Bäcklund transformation of periodic $A_n^{(1)}$
Toda chains is also shown to be integrable and to have a Zakharov–Shabat
pair.
Keywords:combination scattering, Toda chain, Bäcklund transformation, Zakharov–Shabat pair.