Dynamic Tuning of Fabry-Pérot Resonances Based on Femtosecond Laser-Induced Structure-Property Integrated Regulation.

Area of Science:

• Materials Science
• Optics
• Nanotechnology

Background:

• Structural colors offer potential for optical camouflage but achieving dynamic, wide-range color switching remains challenging.
• Existing methods often lack the tunability and reversibility required for adaptive camouflage in changing environments.

Purpose of the Study:

• To propose and demonstrate a structure-property integrated regulation method for achieving wide-range and reversible color tuning in optical camouflage systems.
• To utilize dual-wavelength femtosecond (fs) laser switching to dynamically control optical responses.

Main Methods:

• Fabrication of an asymmetric Fabry-Pérot (F-P) cavity using antimony disulfide (Sb$_{2}$S$_{3}$) and an Al metal layer.
• Employing 1030 nm and 515 nm fs lasers to precisely alter Sb$_{2}$S$_{3}$ film thickness and induce reversible phase changes.
• Introducing grating dispersion via laser-induced periodic surface structures to further expand color tuning range.

Main Results:

• Achieved precise thickness control of Sb$_{2}$S$_{3}$ film (∼2 nm height difference) using the 1030 nm fs laser.
• Demonstrated, for the first time, fs laser-induced crystallization and reversible phase change in Sb$_{2}$S$_{3}$ using the 515 nm laser.
• Expanded the color tuning range to 71.4% sRGB, further enhanced to 106.7% sRGB with grating structures, enabling reversible color switching.

Conclusions:

• The proposed method enables dynamic and reversible color tuning for advanced optical camouflage.
• Femtosecond laser manipulation of Sb$_{2}$S$_{3}$ properties offers a promising pathway for developing adaptive camouflage technologies.
• Integration of F-P cavities, laser-induced phase changes, and grating structures provides a versatile platform for tunable structural colors.