Near Infrared Random Lasing in Multilayer MoS₂.

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Random lasing (RL) is gaining interest for applications in telecommunication, spectroscopy, and biomedical imaging.
• Developing low-threshold, room-temperature random lasers is crucial for practical applications.

Purpose of the Study:

• To demonstrate room-temperature near-infrared (NIR) random lasing (RL) in MoS2/Au nanoparticles (NPs)/ZnO heterostructures.
• To investigate the mechanisms responsible for the observed random lasing.
• To explore the potential of these heterostructures for low-power on-chip NIR random lasers.

Main Methods:

• Fabrication of ~200 nm thick MoS2/Au NPs/ZnO heterostructures.
• Photoluminescence spectroscopy to characterize optical properties and measure lasing thresholds.
• Analysis of structural disorder and material interfaces to understand lasing mechanisms.

Main Results:

• Room-temperature NIR random lasing (800-950 nm) was achieved with a low threshold of ~500 μW.
• Key contributing factors identified: enhanced multiple scattering from disordered Au/ZnO, exciton-plasmon coupling with Au NPs, and charge transfer from ZnO to MoS2.
• Demonstrated the feasibility of using biocompatible materials for NIR random lasers.

Conclusions:

• The MoS2/Au NPs/ZnO heterostructure is a promising platform for efficient room-temperature NIR random lasing.
• The understanding of the underlying mechanisms provides a pathway for designing advanced random laser devices.
• This work paves the way for low-power, biocompatible on-chip NIR random lasers with potential in biomedical applications.