Dromion and multi-soliton structures of the (2+1)-dimensional higher-order Broer-Kaup system

Using the standard truncated Painleve analysis and the Backlund transformation, we can obtain many significant exact soliton solutions of the (2+1)-dimensional higher-order Broer-Kaup (HBK) system. A special type of soliton solution is described by the variable coefficient heat-conduction-like equation. The inclusion of three arbitrary functions in the general expressions of the solitons makes the solitons of the (2+1)-dimensional HBK system possess abundant structures such as solitoff solutions, multi-dromion solutions, ring solitons and so on.