Hybrid Fibers with Subwavelength-Scale Liquid Core for Highly Sensitive Sensing and Enhanced Nonlinearity

Area of Science:

• Photonics and Optofluidics
• Nonlinear Optics
• Optical Sensing

Background:

• Traditional silicon-on-insulator slot waveguides face challenges like high optical losses and short optical paths.
• Developing efficient optofluidic devices requires overcoming these inherent limitations.

Purpose of the Study:

• To propose and investigate a novel subwavelength-scale liquid-core hybrid fiber (LCHF) as an efficient optofluidic waveguide.
• To analyze the waveguide properties and Stimulated Raman Scattering (SRS) effect within the LCHF.

Main Methods:

• Design and theoretical investigation of a liquid-core hybrid fiber (LCHF) using a silica-based hollow-core fiber with a silicon ring and carbon disulfide core.
• Numerical analysis of waveguide properties, including optical power fraction within the core.
• Investigation of the Stimulated Raman Scattering (SRS) effect and modal Raman gain.

Main Results:

• The LCHF achieves a 56.3% fraction of power inside the core, enhancing optical sensing sensitivity.
• A modal Raman gain of 23.60 m⁻¹·W⁻¹ was achieved, twice that of a comparable nanofiber setup.
• The structure demonstrates a significant low-threshold SRS effect due to strong light-matter interaction.

Conclusions:

• The proposed LCHF offers a compact, robust, and flexible in-fiber optofluidic platform.
• This design provides a promising solution for advanced optical sensing and nonlinear optics applications.
• The LCHF presents a novel approach for optofluidic devices with improved performance and ease of implementation.