We have placed a van der Waals homostructure, formed by stacking three two-dimensional layers of WS₂ separated by insulating hBN, similar to a multiple-quantum well structure, inside a microcavity, which facilitates the formation of quasiparticles known as exciton-polaritons. The polaritons are a combination of light and matter, allowing laser emission to be enhanced by nonlinear scattering, as seen in prior polariton lasers. In the experiments reported here, we have observed laser emission with an ultralow threshold. The threshold was approximately 59 nW/μm², with a lasing efficiency of 3.82%. These findings suggest a potential for efficient laser operations using such homostructures.

中文翻译：

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二维多层结构中激子-极化子激光的高效率


我们在微腔内放置了范德华同质结构，该结构是通过堆叠由绝缘 hBN 分隔的三个二维 WS ₂ 层形成的，类似于多量子阱结构，这有利于准粒子的形成称为激子极化子。偏振子是光和物质的组合，允许通过非线性散射增强激光发射，如先前的偏振子激光器中所见。在此报告的实验中，我们观察到具有超低阈值的激光发射。阈值约为 59 nW/μm ² ，激光效率为 3.82%。这些发现表明使用这种同质结构进行高效激光操作的潜力。