MOTION OF A KINK IN A SPATIALLY MODULATED SINE-GORDON SYSTEM

The influence of radiative losses on the velocity-drive characteristic (VDC) of a kink is investigated, by means of perturbation theory, within the framework of a driven damped sine-Gordon equation with an additional term ε{lunate} cos (κ{script}x) sin φ. The main result is that the radiative losses give rise to a sharp step on the VDC near the kink velocity value V = (1 + κ2)-1/2. To obtain this result, it is principally important to take account of a regularizing role of weak dissipation which was neglected earlier. It is demonstrated that hysteretic transitions between the radiative step and a usual dissipation-dominated branch of the VDC may occur. © 1990.