Maskoun Joudi, Gheshlaghi Negar, Isik Furkan, Delikanli Savas, Erdem Onur, Erdem Emine Yegan, Demir Hilmi Volkan
UNAM Institute of Materials Science and Nanotechnology, Bilkent University, Ankara, 06800, Turkey.
LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
Adv Mater. 2021 Mar;33(10):e2007131. doi: 10.1002/adma.202007131. Epub 2021 Jan 25.
The realization of high-quality lasers in microfluidic devices is crucial for numerous applications, including biological and chemical sensors and flow cytometry, and the development of advanced lab-on-chip (LOC) devices. Herein, an ultralow-threshold microfluidic single-mode laser is proposed and demonstrated using an on-chip cavity. CdSe/CdS@Cd Zn S core/crown@gradient-alloyed shell colloidal semiconductor quantum wells (CQWs) dispersed in toluene are employed in the cavity created inside a poly(dimethylsiloxane) (PDMS) microfluidic device using SiO -protected Ag mirrors to achieve in-solution lasing. Lasing from such a microfluidic device having CQWs solution as a microfluidic gain medium is shown for the first time with a record-low optical gain threshold of 17.1 µJ cm ² and lasing threshold of 68.4 µJ cm ² among all solution-based lasing demonstrations. In addition, air-stable SiO protected Ag films are used and designed to form highly tunable and reflective mirrors required to attain a high-quality Fabry-Pérot cavity. These realized record-low thresholds emanate from the high-quality on-chip cavity together with the core/crown@gradient-alloyed shell CQWs having giant gain cross-section and slow Auger rates. This microfabricated CQW laser provides a compact and inexpensive coherent light source for microfluidics and integrated optics covering the visible spectral region.
在微流控设备中实现高质量激光器对于众多应用至关重要，这些应用包括生物和化学传感器、流式细胞术以及先进的芯片实验室（LOC）设备的开发。在此，我们提出并展示了一种使用片上腔的超低阈值微流控单模激光器。将分散在甲苯中的CdSe/CdS@CdZnS核/冠@梯度合金壳胶体半导体量子阱（CQW）用于在聚二甲基硅氧烷（PDMS）微流控设备内部利用SiO保护的Ag镜创建的腔内，以实现溶液内激光发射。在所有基于溶液的激光发射演示中，首次展示了以CQW溶液作为微流控增益介质的这种微流控设备的激光发射，其光学增益阈值低至17.1 μJ/cm²，激光发射阈值为68.4 μJ/cm²。此外，使用并设计了空气稳定的SiO保护的Ag膜，以形成实现高质量法布里 - 珀罗腔所需的高度可调谐且反射的镜子。这些实现的创纪录低阈值源于高质量的片上腔以及具有巨大增益截面和缓慢俄歇速率的核/冠@梯度合金壳CQW。这种微制造的CQW激光器为微流控和集成光学提供了一种紧凑且廉价的相干光源，覆盖可见光谱区域。
