Zero-Dimensional MXene-Based Optical Devices for Ultrafast and Ultranarrow Photonics Applications

Area of Science:

• Materials Science
• Nanotechnology
• Photonics

Background:

• MXene materials are gaining attention for their excellent conductivity, broadband absorption, and tunable band gaps.
• 0D MXene Ti3C2Tx quantum dots offer unique properties for optical applications.

Purpose of the Study:

• To synthesize 0D MXene Ti3C2Tx quantum dots.
• To investigate their nonlinear optical properties and carrier dynamics.
• To demonstrate their application in ultrafast and ultranarrow fiber lasers.

Main Methods:

• Liquid exfoliation for synthesizing 0D MXene Ti3C2Tx quantum dots.
• Nondegenerate transient absorption spectroscopy for carrier dynamics.
• Integration into erbium/ytterbium-doped fiber laser cavities.

Main Results:

• A large nonlinear absorption coefficient (β) of -(11.24 ± 0.14) × 10⁻² cm GW⁻¹ was measured.
• Carrier dynamics showed a maximum TA signal at 1.28 ps.
• Femtosecond lasers with 170 fs pulse durations and 14.8 nm bandwidth were achieved.
• An ultranarrow fiber laser with a 5 kHz FWHM and <0.75% power fluctuation was demonstrated.

Conclusions:

• 0D MXene Ti3C2Tx quantum dots function as effective saturable absorbers (SAs).
• These quantum dots are highly promising for developing advanced ultrafast and ultranarrow photonic devices.