Dispersive radiation and regime switching of oscillating bound solitons in twin-core fibers near zero-dispersion wavelength

We study resonant radiation generated by bound solitons in a twin-core fiber near a zero-dispersion wavelength, in the presence of higher order dispersion terms. We propose a theoretical description of a dispersive wave generation mechanism and derive resonance conditions. The presence of a third order dispersion term leads to generation of polychromatic dispersive radiation and transition from the regime of center-of-mass oscillations to the regime of amplitude oscillations. Such a transition is not reproduced in the case of symmetric fourth order dispersion.