Grating assisted glass fiber coupler for mode selective co-directional coupling

Area of Science:

• Optical Engineering
• Telecommunications Technology
• Materials Science

Background:

• Increasing demand for transmission capacity drives research into space division multiplexing.
• Mode selective fiber couplers are crucial for compatibility with existing glass fiber networks.

Purpose of the Study:

• To present a novel mode selective glass fiber coupler for co-directional coupling.
• To demonstrate the effectiveness of fiber gratings and fused asymmetric fibers in coupler design.

Main Methods:

• Fabrication of a novel mode selective glass fiber coupler.
• Utilizing fiber gratings and fused asymmetric fibers.
• Co-directional coupling mechanism.

Main Results:

• Achieved mode selective coupling efficiency validated by numerical simulations.
• Demonstrated lower mode crosstalk compared to conventional methods.
• Showcased simple adaptation of propagation constants via grating-period adjustment.

Conclusions:

• The developed fiber grating-based coupler is effective for mode selective coupling.
• This approach offers significant advantages in reducing mode crosstalk for optical networks.
• The design allows for straightforward tuning of propagation constants.