Laser miniaturization is one of the hot research topics at present. Recently, a collaborative research team led by Shanghai Institute of Optics and Fine Mechanics (SIOM) of the Chinese Academy of Sciences (CAS), Huazhong University of Science and Technology, and Shenzhen University successfully shrank the single-mode nanolaser to the deep subwavelength scale of ~50 nm in the vertical dimension, using quasi-two-dimensional perovskites as gain medium and sandwich structured cavity with only a layer of ultraviolet glue and a glass substrate.

The work entitled “Subwavelength-Polarized Quasi-Two-Dimensional Perovskite Single-Mode Nanolaser” was published in ACS Nano on April 6, 2021.

In this study, researchers investigated the excitonic gain nature of quasi-two-dimensional perovskites and revealed the contribution of singlet excitons, triplet excitons, and polarons to the high net gain of 558 cm^-1 with a long lifetime of ~50 ps.

Inspired by the gain characteristic, a vertical cavity was simplified and successfully shrank to the deep subwavelength scale using only ultraviolet glue and a glass substrate. Even though the physical thickness of the perovskite gain medium is only ～40 nm, the stable and highly linearly polarized (up to ~81%) single-mode lasing with a pulse duration of 26.5 ps was achieved at room temperature, with a low threshold of ~143 μJ/cm² and ~10.5 μJ/cm² under two- and one-photon excitation, respectively. Especially, the laser Q factor was up to 1635, among the largest values in perovskite vertical cavities.

Above these findings, researchers suggest that the simple structure and deep subwavelength-scale quasi-Two-Dimensional perovskites laser could provide an effective strategy for achieving electrically driven perovskite lasers and integrate the miniaturized light source on chips in the future.

In 2018, the same team reduced the size of perovskite laser to subwavelength scale for the first time [ACS Nano 2018, 12 (6), 5923-5931]. In this latest work, they further shrank the laser size to the deep-subwavelength scale for the first time. The high-performance “sandwich” perovskite laser would provide a versatile platform for electrically driven chip-level coherent light sources for nanophotonic applications and next-generation integrated laser sources.

This work was supported by the Strategic Priority Research Program of CAS, National Natural Science Foundation of China, and China Postdoctoral Science Foundation.

Luminescence kinetics and laser properties of the quasi-two-dimensional perovskite thin films. (Image by SIOM)

Article website:
https://doi.org/10.1021/acsnano.0c10647

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/