Integrated liquid-core optical fibers for ultra-efficient nonlinear liquid photonics

Area of Science:

• Photonics
• Nonlinear Optics
• Materials Science

Background:

• Liquid-based photonic devices offer unique nonlinear properties.
• Integrating liquid core optical fibers (LCOF) with standard fibers has been a significant challenge.
• Previous liquid-photonic applications were limited by integration difficulties and high power requirements.

Purpose of the Study:

• To develop a novel, fully integrated platform for liquid photonics.
• To demonstrate ultralow threshold nonlinear optical phenomena using this integrated platform.
• To explore the potential of LCOF for advanced photonic applications.

Main Methods:

• Fusion splicing LCOF with standard single-mode optical fiber to create an integrated platform.
• Utilizing carbon disulfide (CS₂) filled LCOF for Raman generation experiments.
• Pumping the LCOF with sub-nanosecond pulses at 532 nm and 1064 nm.

Main Results:

• Achieved ultralow threshold Raman generation with Stokes generation at an energy threshold of 1 nJ.
• Demonstrated an energy threshold approximately three orders of magnitude lower than previous reports using hydrogen gas.
• Successfully integrated LCOF with standard optical fibers, overcoming a major practical hurdle.

Conclusions:

• The integrated LCOF platform is practical and enables ultralow power nonlinear optics.
• This technology opens avenues for efficient white light generation, mid-IR generation, and all-optical switching.
• The platform leverages the high optical nonlinearities of liquids for advanced photonic device development.