“…Equation (4) is a generalized cubic‐quintic NLS equation with cubic derivative terms. It is known to govern the propagation of ultrashort pulses in a single‐mode optical fiber, [ 47 ] the modulations of weakly nonlinear ions in acoustic plasma waves, [ 48 ] ferromagnetic chain, [ 49 ] evolutions of Stokes waves, [ 50 ] soliton propagation in optical fibers, and metamaterials, [ 51,52 ] etc. Equation (4) can also be applied to the description of high‐intensity pulse propagation, [ 53 ] controllable self‐steepening, [ 54 ] and generation of Cherenkov radiation [ 55 ] in quadratic crystals.…”