Thickness‐ and Wavelength‐Dependent Nonlinear Optical Absorption in 2D Layered MXene Films

• Published in: Small science Vol. 4; no. 8
• Main Authors: Jin, Di, Liu, Wenbo, Jia, Linnan, Zhang, Yuning, Hu, Junkai, El Dirani, Houssein, Kerdiles, Sébastien, Sciancalepore, Corrado, Demongodin, Pierre, Grillet, Christian, Monat, Christelle, Huang, Duan, Wu, Jiayang, Jia, Baohua, Moss, David J.
• Format: Journal Article
• Language: English
• Published: Weinheim John Wiley & Sons, Inc 01-08-2024; Wiley; Wiley-VCH
• Subjects: 2D materials; Engineering Sciences; Graphene; Lasers; Micro and nanotechnologies; Microelectronics; MXenes; nonlinear optics; on‐chip integrations; Optical properties; Optics; Polymers; Silicon nitride; Z‐scan technique; nonlinear optics; Z-scan technique; on-chip integrations; MXenes; 2D materials
• ISSN: 2688-4046; 2688-4046
• DOI: 10.1002/smsc.202400179

As a rapidly expanding family of 2D materials, MXenes have recently gained considerable attention. Herein, by developing a coating method that enables transfer‐free and layer‐by‐layer film coating, the nonlinear optical absorption (NOA) of Ti3C2Tx MXene films is investigated. Using the Z‐scan technique, the NOA of the MXene films is characterized at ≈800 nm. The results show that there is a strong and layer‐dependent NOA behavior, transitioning from reverse saturable absorption (RSA) to saturable absorption (SA) as the layer number increases from 5 to 30. Notably, the nonlinear absorption coefficient β changes significantly from ≈7.13 × 102 cm GW−1 to ≈−2.69 × 102 cm GW−1 within this range. The power‐dependent NOA of the MXene films is also characterized, and a decreasing trend in β is observed for increasing laser intensity. Finally, the NOA of 2D MXene films at ≈1550 nm is characterized by integrating them onto silicon nitride waveguides, where an SA behavior is observed for the films including 5 and 10 layers of MXene, in contrast to the RSA observed at ≈800 nm. These results reveal intriguing nonlinear optical properties of 2D MXene films, highlighting their versatility and potential for implementing high‐performance nonlinear photonic devices.
Nonlinear optical absorption (NOA) behaviors of 2D layered MXene films are characterized using both the Z‐scan technique and by integrating them onto silicon nitride photonic waveguides. Experimental results show that the NOA varies significantly as the light wavelength and film thickness changes, highlighting the versatility and potential of 2D MXene films for implementing high‐performance nonlinear photonic devices.