Supermode fiber for orbital angular momentum (OAM) transmission

Area of Science:

• Optical Fiber Communications
• Photonics
• Waveguide Engineering

Background:

• Orbital-angular-momentum (OAM) modes offer potential for increased data capacity in optical communications.
• Existing fiber structures face challenges in efficiently supporting and controlling multiple OAM modes.
• Strong coupling between cores is necessary for generating OAM supermodes in multi-core fibers.

Purpose of the Study:

• To design and analyze a novel multi-orbital-angular-momentum (OAM) multi-core supermode fiber (MOMCSF).
• To investigate the impact of core pitch and core number on OAM mode characteristics.
• To optimize the fiber design for low mode coupling, low nonlinearity, and low modal dependent loss.

Main Methods:

• Fabrication of a multi-core supermode fiber with equally-spaced, circularly-arranged cores.
• Analysis of OAM mode characteristics using varying core pitches and core numbers.
• Optimization of fiber design parameters to control mode coupling and nonlinearity.

Main Results:

• The designed MOMCSF supports the transmission of multiple OAM modes.
• Favorable performance metrics including low mode coupling were achieved.
• Low nonlinearity and low modal dependent loss were demonstrated for the transmitted OAM modes.

Conclusions:

• The developed MOMCSF is a promising platform for high-capacity optical communication systems.
• The design allows for effective control over OAM mode propagation.
• This fiber architecture offers a viable solution for overcoming limitations in current OAM mode transmission.