$CPT$-symmetric coupler with intermodal dispersion

摘要: A dual-core waveguide with balanced gain and loss in different arms intermodal coupling is considered. The system not invariant under the conventional $PT$ symmetry but obeys $CPT$ where an additional spatial inversion $C$ corresponds to swapping coupler arms. We show that second-order dispersion of allows for unbroken supports propagation stable vector solitons along coupler. Small-amplitude are found explicit form. combined effect gain-and-loss dispersive results several interesting features which include a separation between components arms, nontrivial dependence stability soliton on its velocity, existence more complex stationary two-hump solutions. Unusual decay dynamics unstable discussed too.