Recently, a research team from Shanghai Institute of Optics and Fine Mechanics of the Chinese Academy of Sciences, has developed a new technical solution – ‘CQD-assembly optical microsphere cavity’ embedded in the silica matrix, which can fight against the multi-level challenges in high-temperature stable micro-/nanolasers research. The result was published in Light: Science & Applications on Mar. 18, 2021.

In their experiment, researchers developed close-packed CQD-assembled microspheres and embedded them in a silica matrix through the rapid self-aggregation and solidification of CdSe/ZnS CQD. This technology addresses the core issues of photoluminescence (PL) quenching effect and low optical gain in traditional CQD laser research.

High-efficiency low-threshold CQD microlasers are demonstrated together with long-playing (40 min) working stability even at 450 K under pulsed laser excitation, which is the highest operational temperature for CQD lasers. Moreover, single-mode CQD microlasers are obtained with tunable wavelengths across the entire visible spectral range.

The heat dissipation problem is an intrinsic and inevitable difficulty for the next generation of highly-integrated optoelectronic devices. This work contributes a direct solution by achieving the stable high-temperature operation ability for the miniaturized components.

Moreover, this innovative solution-processable method does not require complex optical cavity processing, which is easy to operate, controllable, and easily mass-produced. CQD microlasers can be highly integrated into a micro-substrate, promising for ultra-bright economical on-chip light sources. In conclusion, researchers find a unique way to break through the predicament of the CQD laser research, and substantively promote its development stage from the basal performance study to the senior practical compatibility for high-temperature low-cost microlasers and predictable commercialization.

This work was supported by the National Natural Science Foundation of China, and the Youth Top-notch Talent Support Program in Shanghai.

Fig. 1. The three core problems of CQD laser research and the corresponding solutions for achieving high-temperature CQD lasers. (Image by SIOM)

Fig. 2. High-density integrated lasers and broad wavelength-tunable single-mode lasers at high temperature based on CQDAMs. (Image by SIOM)

Article website:
https://doi.org/10.1038/s41377-021-00508-7

Contact:
WU Xiufeng
General Administrative Office
Shanghai Institute of Optics and Fine Mechanics, CAS
Email: xfwu@siom.ac.cn
Web: http://english.siom.cas.cn/