Lasing from Laminated Quasi-2D/3D Perovskite Planar Heterostructures

Planar heterostructures are widely used in commercial III-V semiconductor lasers, but not yet explored for perovskite gain media. This study investigates the gain performance of a CsPbBr3(BABr)(x)/CsPbBr3 (quasi-2D/3D) perovskite planar heterostructure fabricated by lamination. The resulting heterostructure is designed to enhance the photon and excited-state density in a non-quantum-confined thin 3D layer (30 nm) by simultaneously 1) confining the optical mode and 2) supporting excited-state transfer from the wider-bandgap quasi-2D perovskite to the lower-bandgap 3D perovskite. This allows the low amplified spontaneous emission (ASE) threshold of 150 (+/- 20) mu J cm(-2) and lasing threshold of 46 (+/- 15) mu J cm(-2) to be realized in such a heterostructure under nanosecond pumping. Further modeling reveals that the ASE performance can be significantly improved via maximizing the excited-state transfer efficiency (only 14% for current prototypes) and highlights the potential of perovskite planar heterostructures as high-performance gain media.