Huang Zhigao, Ren Yinjuan, Wu Yiming, Qin Jiajun, Jiao Kerong, Zhang Hao, Ta Van Duong, Gao Feng, Shen Hua, Wang Yue
School of Microelectronics, College of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
School of Science, Nanjing University of Posts and Telecommunications, Nanjing, 210023, China.
Adv Mater. 2025 Aug 6:e09457. doi: 10.1002/adma.202509457.
Sustained amplified stimulated emission (ASE) under continuous-wave (cw) excitation is a prerequisite for any new gain material being developed for lasing applications. Despite the great success achieved in colloidal quantum dot (QD) lasers, the cw light amplification is hampered by the high pump threshold and thermal effects of QD solids. Herein, the first-ever cw ASE and lasing from QDs relevant for practical implementations are realized by adopting the microfluidic dot-in-matrix design. Leveraging on the transient and steady-state gain spectroscopy, it is demonstrated that the high-concentration dispersed QDs with a gain feature customized for cw pumping render the low pump threshold (≈340 W cm). Meanwhile, the QD micro-liquids effectively dissipate the heat arising from the nonradiative multi-carrier recombination. As such, the unprecedented two-band cw ASE and long-lasting cw lasing with coherent output beam are realized. The findings open the door to practical QD lasers and may unlock new possibilities in optofluidics and optoelectronics.
在连续波（cw）激发下实现持续的放大受激辐射（ASE）是为激光应用开发任何新型增益材料的前提条件。尽管胶体量子点（QD）激光器取得了巨大成功，但cw光放大受到QD固体的高泵浦阈值和热效应的阻碍。在此，通过采用微流控点矩阵设计，首次实现了与实际应用相关的量子点的连续波ASE和激光发射。利用瞬态和稳态增益光谱，证明了具有为连续波泵浦定制的增益特性的高浓度分散量子点具有低泵浦阈值（≈340 W cm）。同时，量子点微液体有效地消散了非辐射多载流子复合产生的热量。因此，实现了前所未有的双波段连续波ASE和具有相干输出光束的持久连续波激光发射。这些发现为实用的量子点激光器打开了大门，并可能在光流体学和光电子学中解锁新可能性。
