Low threshold and highly polarized amplified spontaneous emission in Quasi-2D Dion-Jacobson perovskite

Quantum-well-structured quasi-2D perovskites are considered promising candidates gain media towards on-chip nanolasers thanks to their excellent optical stability and tunability. However, achieving low-threshold, high-gain amplified spontaneous emission (ASE) in quasi-2D perovskite thin films remains challenging. In this study, we successfully prepared smooth and compact all-inorganic quasi-2D perovskite thin films using a polymer doping strategy. We achieved low-threshold, high-gain ASE in Dion-Jacobson (DJ) perovskite thin films. The ASE threshold was as low as 4.8 mu J/cm2, with the gain factor reaching 1454 cm-1 (10 Pth). More importantly, the ASE behaved excellent linear polarization characteristics with a degree of polarization of 96 % in the polymer-doped DJ perovskite films. This high polarization can be attributed to the significant enhancement of the vertical alignment of transition dipole moments (TDM) induced by the polymer. Similar outstanding ASE performance was also achieved in other quasi-2D perovskite films after polymer doping, which demonstrated the universality of polymer additives on modulation of the polarized stimulated emission in quasi-2D perovskite thin films.