Dion-Jacobson (DJ) structured quasi-2D perovskites are promising candidates for new generation gain medium due to their excellent photoelectric performance, super environmental, and structure stability. The isolated carrier recombination with inhomogeneous mixed phase is detrimental in enhancing amplified spontaneous emission (ASE) of optically pumped DJ phase quasi-2D perovskites lasers. Here, in 1.3-propanediamine (PDA)-based DJ perovskites, the carrier dynamic behavior from the pristine sample to the Cremophor EL (Cre EL) treated sample is unraveled. Remarkably, the Cre EL treated sample displays a well-proportioned large n domain distribution, resulting in an increased radiation-state density and hence enhancing collaboration emitting between carriers. The improved collaboration emitting promotes carriers' fast relay radiation, resulting in a higher ASE performance with a threshold reduced from 11.7 to 4.8μJ/cm2, optical gain coefficient increased from 775 to 1559 cm-1 and degree-of-polarization (DOP) improved from 0.59 to 0.98. Our findings suggest that the development of DJ structured quasi-2D perovskite laser gain medium should target facilitating fast carrier co-radiation recombination.