Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, People's Republic of China.
School of New Energy and Materials, State Key Laboratory of Oil and Gas Reservoir and Exploitation, Southwest Petroleum University, Chengdu 610500, People's Republic of China.
ACS Appl Mater Interfaces. 2023 Apr 19;15(15):19330-19336. doi: 10.1021/acsami.2c21648. Epub 2023 Apr 5.
I-III-VI ternary quantum dots (QDs) have emerged as favorable alternatives to the toxic II-VI QDs for optoelectronic and biological applications. However, their use as optical gain media for microlasers is still limited by a low fluorescence efficiency. Here, we demonstrate amplified spontaneous emission (ASE) and lasing from colloidal QDs of Zn-processed AgInS (AIS) for the first time. The passivation treatment on the AIS QDs yields a 3.4-fold enhancement of fluorescence quantum efficiency and a 30% increase in the two-photon absorption cross section. ASE is achieved from the AIS/ZnS core/shell QD films under both one- and two-photon pumping with a threshold fluence of ∼84.5 μJ/cm and 3.1 mJ/cm, respectively. These thresholds are comparable to the best optical gain performance of Cd based-QDs reported in the literature. Moreover, we demonstrate a facile whispering-gallery-mode microlaser of the core/shell QDs with a lasing threshold of ∼233 μJ/cm. The passivated AIS QDs can be promising optical gain media for photonic applications.
I-III-VI 型量子点 (QDs) 作为光电和生物应用中有毒的 II-VI QDs 的替代品而崭露头角。然而，它们作为微激光器的光学增益介质的应用仍然受到荧光效率低的限制。在这里，我们首次展示了胶体量子点的放大自发发射 (ASE) 和激光。AIS QDs 的钝化处理使荧光量子效率提高了 3.4 倍，双光子吸收截面增加了 30%。在单光子和双光子泵浦下，AIS/ZnS 核/壳 QD 薄膜均可实现 ASE，其阈值分别为约 84.5 μJ/cm 和 3.1 mJ/cm。这些阈值与文献中报道的基于 Cd 的 QDs 的最佳光学增益性能相当。此外，我们还展示了具有约 233 μJ/cm 的激光阈值的核/壳 QD 的简单 whispering-gallery-mode 微激光器。钝化后的 AIS QDs 有望成为光子应用的光学增益介质。
