Continuous-wave operation of electrically driven single mode microlaser

Developing current-driven single-mode micro-/nanolasers is highly desirable for various practical applications, but still faces severe challenges. Herein, a continuous-wave operation of an electrically driven laser device using a Ga-incorporated n-type ZnO microwire, MgO nanofilm, and p-type GaAs substrate is demonstrated. The device can enable a single-mode lasing peaking at 820 nm and a narrow linewidth of about 0.4 nm, and the quality factor Q is evaluated to 2000. The presence of a distinct threshold, sharp linewidth reduction, and polarized coherent illumination provides conclusive evidence for achieving lasing oscillation. Relative polaritonic features are further proofed; thus, single-mode lasing feature should be ascribed to the exciton–polariton. The results can enable a workable avenue to realize near-infrared micro-/nanolaser diodes for high-efficiency coherent light sources, which are no longer limited by conventional narrow-bandgap semiconductors.