Vector breathers, rogue and breather-rogue waves for a coupled mixed derivative nonlinear Schrödinger system in an optical fiber

In this paper, a coupled mixed derivative nonlinear Schrödinger system, which describes the short pulses in the femtosecond or picosecond regime of a birefringent optical fiber, is investigated. Based on the known Nth-order breather solutions, we derive the first-order breathers and investigate their properties, e.g., velocities and peak amplitudes, where N is a positive integer. Then, two kinds of the second-order breathers are presented. We construct the Nth-order semirational solutions, with only one spectral parameter involved. Based on the obtained Nth-order semirational solutions, we analytically investigate and graphically illustrate the vector degenerate breathers, rogue and breather-rogue waves. We discuss how certain parameters, e.g., the nonlinear coefficients, affect the shapes of the degenerate breathers, rogue and breather-rogue waves.