Nonlinear dynamics of a quasi-one-dimensional helicoidal structure

Abstract

We analytically describe solitons and spin waves in the helicoidal structure of magnets without an inversion center using the “dressing” method in the framework of the sine-Gordon model. Analyzing the nonlinear dynamics of spin waves in the helicoidal-structure background reduces to solving linear integral equations on a Riemann surface generated by the superstructure. We obtain spectral expansions of integrals of motion with the soliton and spin-wave contributions separated.