Room-temperature Continuous-wave Lasing from Monolayer Molybdenum Ditelluride with a Silicon Nanobeam Cavity

摘要

Monolayer transition metal dichalcogenides (TMDs) provide the most efficientoptical gain materials and have potential for making nanolasers with thesmallest gain media with lowest energy consumption. But lasing demonstrationsbased on TMDs have so far been limited to low temperatures. Here, wedemonstrate the first room-temperature laser operation in the infraredwavelengths from a monolayer of molybdenum ditelluride on a siliconphotonic-crystal nanobeam cavity. Our demonstration is made possible by aunique choice of TMD material with emission wavelength below siliconabsorption, combined with the high Q-cavity design by silicon nanobeam. Lasingat 1132 nm is demonstrated at room-temperature pumped by a continuous-wavelaser, with a threshold density at 6.6 W/cm2. The room-temperature linewidth of0.202 nm is the narrowest with the corresponding Q of 5603, the largestobserved for a TMD laser. This demonstration establishes TMDs as practicalnanolaser materials. The silicon structures provide additional benefits forsilicon-compatible nanophotonic applications in the important infraredwavelengths.