Perovskite Quantum Dots Lasing in Double-Heterostructure through Energy Transfer.

Chu, Zihao; Li, Yang; Cong, Riyu; Mao, Xinrui; Li, Yanping; Xu, Wanjin; Gao, Yunan; Ran, Guangzhao · Nano Lett · 2024

basic_science · Level V

Where this comes from

Abstract

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)<sub>2</sub>Cs<sub><i>n</i>-1</sub>Pb<sub><i>n</i></sub>X<sub>3<i>n</i>+1</sub> (quasi-2D)/CsPbBr<sub>3</sub> 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/cm<sup>2</sup> 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.