Enhanced fast light in microfiber ring resonator with a Sagnac loop reflector

Area of Science:

• Photonics
• Optical Engineering
• Materials Science

Background:

• Microfiber knot resonators are used for optical sensing and filtering.
• Controlling light velocity is crucial for advanced optical communication systems.
• Sagnac loop reflectors offer unique light manipulation properties.

Purpose of the Study:

• To fabricate and investigate a microfiber knot-type ring resonator incorporating a Sagnac loop reflector.
• To control light velocity and demonstrate pulse advancement using this novel optical device.
• To enhance transmission and group delay compared to conventional microfiber ring resonators.

Main Methods:

• Fabrication of a microfiber knot-type ring resonator with an integrated Sagnac loop.
• Experimental demonstration of pulse advancement using an under-coupled resonator configuration.
• Characterization of the device's performance with a 5-Gb/s RZ (return-to-zero) signal.

Main Results:

• The fabricated device exhibited doubled transmission and group delay due to the Sagnac loop.
• A maximum pulse advancement of approximately 25 picoseconds was experimentally achieved.
• The device successfully controlled light velocity, enabling pulse advancement.

Conclusions:

• The microfiber knot-type ring resonator with a Sagnac loop reflector is an effective device for controlling light velocity.
• This technology shows promise for applications in optical signal processing and high-speed communications.
• The demonstrated pulse advancement opens avenues for novel photonic device designs.