ITO electrode-embedded double-cladding single-crystal LiNbO3 optical fiber

Area of Science:

• Materials Science
• Optoelectronics
• Fiber Optics

Background:

• Single-crystal optical fibers offer unique electro-optic properties.
• Integration of electrodes within optical fibers is crucial for device functionality.
• Existing fabrication methods for such devices can be complex and inefficient.

Purpose of the Study:

• To demonstrate a novel method for fabricating single-crystal lithium niobate (LiNbO3) optical fibers.
• To integrate indium tin oxide (ITO) electrodes within the fiber structure.
• To characterize the electro-optic performance and optical loss of the fabricated fibers.

Main Methods:

• Utilized the CO2 laser-heated pedestal growth technique for a one-step drawing process.
• Embedded ITO electrodes between the LiNbO3 core and silica glass cladding.
• Fabricated optical fibers with a core diameter of 9 μm and electrode distance of 50 μm.

Main Results:

• Achieved a low half-wave voltage (Vπ) of 6.6 V.
• Demonstrated a high effective electro-optic coefficient of 23.6 pm/V.
• Measured a low transmission loss of 0.89 dB/cm.

Conclusions:

• The one-step drawing process successfully produced single-crystal LiNbO3 optical fibers with embedded ITO electrodes.
• The fabricated fibers exhibit excellent electro-optic performance and low optical loss.
• This technique is adaptable for other single-crystal core fibers, paving the way for advanced electrically tunable fiber devices.