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

TL;DR

This paper reports the first room-temperature continuous-wave lasing from a monolayer molybdenum ditelluride integrated with a silicon nanobeam cavity, demonstrating practical TMD-based nanolasers in the infrared.

Contribution

It introduces a novel room-temperature TMD nanolaser operating at 1132 nm with high Q-factor, combining TMD material choice and silicon nanobeam cavity design.

Findings

Lasing achieved at 1132 nm wavelength at room temperature.

Threshold pump power density of 6.6 W/cm².

Record narrow linewidth of 0.202 nm with Q of 5603.

Abstract

Monolayer transition metal dichalcogenides (TMDs) provide the most efficient optical gain materials and have potential for making nanolasers with the smallest gain media with lowest energy consumption. But lasing demonstrations based on TMDs have so far been limited to low temperatures. Here, we demonstrate the first room-temperature laser operation in the infrared wavelengths from a monolayer of molybdenum ditelluride on a silicon photonic-crystal nanobeam cavity. Our demonstration is made possible by a unique choice of TMD material with emission wavelength below silicon absorption, combined with the high Q-cavity design by silicon nanobeam. Lasing at 1132 nm is demonstrated at room-temperature pumped by a continuous-wave laser, with a threshold density at 6.6 W/cm2. The room-temperature linewidth of 0.202 nm is the narrowest with the corresponding Q of 5603, the largest observed for a TMD laser. This demonstration establishes TMDs as practical nanolaser materials. The silicon structures provide additional benefits for silicon-compatible nanophotonic applications in the important infrared wavelengths.