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Solid-state perovskites have recently emerged as promising coherent light sources, due to their efficient gain. While the continuous-wave (CW) optically pumped perovskite laser has been achieved at low temperatures, the final frontier of an electrical perovskite-based laser diode remains challenging due to the heat management and intrinsic instability of perovskite materials. Here, we demonstrate waterproof perovskite-hexagonal boron nitride (hBN) hybrid nanolasers with low lasing thresholds and high operating temperature. After capping with the hBN flake, which possesses superb and anisotropic thermal conductivity, heat dissipation of the perovskite nanolaser is accelerated and an overheated hot spot is avoided. This results in the significant reduction of lasing thresholds (17.05% to 60.15%) in 16 measured samples and clear lasing behavior under a temperature as high as 75.6 °C. Moreover, hBN with high environmental stability can effectively protect the perovskite from the polar solvents. The hBN encapsulated CsPbI 3 nanolaser can incessantly lase in water for an hour, and the lasing behavior can be retained even after 24 h of immersion in water. The reduction of lasing threshold, improved heat removal, and higher temperature tolerance of the hybrid structure nanolaser marks a major step toward a CWpumped perovskite laser at room temperature, while also allowing perovskites to be integrated into high power density optoelectronic devices and future electrically driven lasers. In addition, as the sandwiching of perovskites with hBN can withstand polar solvents, this method may serve as a reliable method for both the future fabrication of perovskite-based devices and sensor-based applications in solvent systems.

The integration of on-chip dielectric lasers and subwavelength plasmonic waveguides has attracted enormous attention because of the combination of both the advantages of the high performances of the small dielectric lasers and the subwavelength plasmonic waveguides. However, the configurable integration is still a challenge owing to the complexity of the hybrid structures and the damageability of the gain media in the multistep micro/nanofabrications. By employing the dark-field optical imaging technique with a position uncertainty of about 21 nm and combining the high-resolution electron beam lithography, the small colloidal quantum dot (CQD) lasers without any damages are accurately aligned with the silver nanowires. As a result, the integration of the CQD lasers and the silver nanowires can be flexibly configured on chips. In the experiment, the tangential coupling, radial coupling, and complex coupling between the high-performance CQD lasers and the subwavelength silver nanowires are demonstrated. Because of the subwavelength field confinements of the silver nanowires, the deep-subwavelength coherent sources (multimode, one-color single-mode, or two-color single-mode) with a mode area of only 0.008λ are output from these hybrid structures. This configurable on-chip integration with high flexibility and controllability will greatly facilitate the developments of the complex functional hybrid photonic-plasmonic circuits.

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