Color generation and refractive index sensing using diffraction from 2D silicon nanowire arrays

Area of Science:

• Nanotechnology
• Optics
• Materials Science

Background:

• Structural color generation is crucial for advanced optical applications.
• Silicon nanowires offer a versatile platform for nanophotonic devices.
• Controlling color through nanostructure design is an active research area.

Purpose of the Study:

• To demonstrate tunable structural color generation using silicon nanowires.
• To develop a cost-effective refractive index sensor based on silicon nanowire arrays.
• To investigate the relationship between structural parameters and generated colors.

Main Methods:

• Fabrication of vertical silicon nanowires in square lattices.
• Utilizing Bragg diffraction theory to predict and control structural color.
• Employing trichromatic RGB decomposition for refractive index sensing.
• Performing image processing and spectral analysis for enhanced resolution.

Main Results:

• Achieved tunable structural colors from red to blue by adjusting lattice spacing.
• Demonstrated color generation across the visible spectrum from a single lattice.
• Developed a refractive index sensor with a resolution of 10⁻⁴ using basic image processing.
• Attained a refractive index resolution of 10⁻⁶ with spectral analysis and high sensitivity.

Conclusions:

• Silicon nanowire arrays provide a simple and effective method for generating tunable structural colors.
• The developed sensor is cost-effective, label-free, and offers high refractive index resolution.
• This technology has potential applications in sensing, displays, and optical devices.