Ultralarge anti-Stokes lasing through tandem upconversion.

Area of Science:

• Photonics and Nanotechnology
• Materials Science

Background:

• Direct deep-ultraviolet (UV) laser generation faces challenges in fabrication and cost.
• UV light is crucial for environmental and life science applications.

Purpose of the Study:

• To present a strategy for indirect deep-UV lasing using tandem upconversion.
• To develop a core-shell-shell nanoparticle for efficient UV emission.

Main Methods:

• Fabrication of a core-shell-shell nanoparticle integrating distinct upconversion processes.
• Utilizing a tandem upconversion process for an ultralarge anti-Stokes shift.
• Incorporating nanoparticles into a toroid microcavity for lasing.

Main Results:

• Achieved deep-UV emission at 290 nm via excitation at 1550 nm telecommunication wavelengths.
• Demonstrated an ultralarge anti-Stokes shift of 1260 nm (~3.5 eV).
• Realized single-mode lasing at 289.2 nm using the nanoparticle gain medium.

Conclusions:

• The tandem upconversion strategy provides a viable route for indirect deep-UV lasing.
• The developed nanoparticle offers a cost-effective and miniaturized solution for short-wavelength lasers.
• Leveraging telecommunication industry components facilitates practical device applications.