Planar double heterostructures were initially investigated and have been successfully applied in III–V semiconductor lasers due to their excellent roles in confining both the photons and carriers. Here, we design and fabricate a (PEA)₂Cs_n–1Pb_nX_3n+1 (quasi-2D)/CsPbBr₃ QD/quasi-2D double-heterostructure sandwiched in a 3/2 λ DBR microcavity, and then demonstrate a single-mode pure-green lasing with a threshold of 53.7 μJ/cm² under nanosecond-pulsed optical pumping. The thresholds of these heterostructure devices decrease statistically by about 50% compared to the control group with no energy donor layers, PMMA/QD/PMMA in an identical microcavity. We show that there is efficient energy transfer from the barrier regions of the quasi-2D phases to the QD layer by transient absorption and luminescence lifetime spectra and that such energy transfer leads to marked threshold reduction. This work indicates that the double-heterostructure configurations should play a significant role in the future perovskite electrically pumped laser.

中文翻译：

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钙钛矿量子点通过能量转移在双异质结构中发射激光


平面双异质结构最初被研究，并因其在限制光子和载流子方面的出色作用而成功应用于 III-V 族半导体激光器。在这里，我们设计并制造了 (PEA) ₂ Cs _n–1 Pb _n X _3n+1 （准二维）/CsPbBr ₃ 将QD/准2D双异质结构夹在3/2 λ DBR微腔中，然后在53.7 μJ/cm ² 下展示阈值53.7 μJ/cm的单模纯绿光激光纳秒脉冲光泵浦。与相同微腔中没有能量供体层、PMMA/QD/PMMA 的对照组相比，这些异质结构器件的阈值统计上降低了约 50%。我们通过瞬态吸收和发光寿命光谱表明，从准二维相的势垒区域到量子点层存在有效的能量转移，并且这种能量转移导致阈值显着降低。这项工作表明，双异质结构配置应该在未来的钙钛矿电泵浦激光器中发挥重要作用。