Constrained by the large mode loss, it is a challenge to achieve low threshold lasing in a thin nanowire whispering-gallery-mode (WGM) cavity at room temperature (RT). Here, we demonstrate low threshold single-mode polariton lasing at RT in a thin ZnO nanowire (165 nm in diameter) on Al₂O₃ layer/rough Ag film. Such a structure can compensate the whispering-gallery mode loss and enhance the WGM polariton emission in UV region for subwavelength ZnO nanowires. They are attributed to the strong local electromagnetic field near nanowire induced by Ag film. The polariton lasing is confirmed by the low threshold, narrowing of the linewidth at threshold, nonlinear intensity-power dependence and continous blueshift of the emission. A clear transition from strong coupling regime to weak coupling regime is observed with increasing pump power. This work suggests low-cost and high-performance room-temperature nanolasers or polariton devices achieved in single thin ZnO nanowires.

受较大模式损耗的约束，在室温（RT）下在细纳米线耳语画廊模式（WGM）腔中实现低阈值激光发射是一个挑战。在这里，我们展示了在Al ₂ O ₃上的细ZnO纳米线（直径165 nm）中在RT处的低阈值单模极化激射。层/粗糙的Ag膜。对于亚波长ZnO纳米线，这种结构可以补偿回音壁模式损失并增强UV区域中的WGM极化子发射。它们归因于银膜在纳米线附近产生的强局部电磁场。通过低阈值，阈值处的线宽变窄，非线性强度-功率相关性以及发射的连续蓝移来确认极化激射。随着泵浦功率的增加，观察到了从强耦合状态到弱耦合状态的清晰过渡。这项工作提出了在单根薄ZnO纳米线中实现的低成本，高性能的室温纳米激光或极化子器件。