Monolayer transition-metal dichalcogenides (TMDs) have the potential to become efficient optical-gain materials for low-energy-consumption nanolasers with the smallest gain media because of strong excitonic emission. However, until now TMD-based lasing has been realized only at low temperatures. Here we demonstrate for the first time a room-temperature laser operation in the infrared region from a monolayer of molybdenum ditelluride on a silicon photonic-crystal cavity. The observation is enabled by the unique combination of a TMD monolayer with an emission wavelength transparent to silicon, and a high-Q cavity of the silicon nanobeam. The laser is pumped by a continuous-wave excitation, with a threshold density of 6.6 W cm^–2. Its linewidth is as narrow as 0.202 nm with a corresponding Q of 5,603, the largest value reported for a TMD laser. This demonstration establishes TMDs as practical materials for integrated TMD–silicon nanolasers suitable for silicon-based nanophotonic applications in silicon-transparent wavelengths.

由于强激子发射，单层过渡金属二硫属化合物（TMD）可能成为具有最小增益介质的低能耗纳米激光的高效光学增益材料。但是，到目前为止，仅在低温下才实现基于TMD的激光。在这里，我们首次展示了硅光子晶体腔上单层二碲化钼在红外区的室温激光操作。可以通过将TMD单层和对硅透明的发射波长与硅纳米束的高Q腔进行独特的组合来进行观察。激光由连续波激发泵浦，其阈值密度为6.6 W cm ^–2。其线宽窄至0.202 nm，相应的Q为5,603，这是TMD激光器的最大值。该演示将TMD确立为适用于硅透明波长中基于硅的纳米光子应用的集成TMD-硅纳米激光器的实用材料。