Low cross talk crescent-shaped pore-assisted few-mode multi-core optical fiber for optical communication

In this paper, we propose a crescent-shaped pore-assisted structure to realize a few-mode multi-core (four-mode six-core) optical fiber with low inter-core cross talk for large-capacity long-distance communication. Using the finite element method, a theoretical analysis is conducted at a working wavelength of 1550 nm, where the proposed optical fiber achieves a total loss of less than 0.2 dB/km and an effective mode field area of greater than 108 µ m 2 . The inter-core cross talk of the fiber is less than − 56 d B / 100 k m , and the relative multiplexing factor reaches up to 28.3, which significantly increases the core density. The maximum dispersion of the four supported linear polarization modes is less than 5.85 p s / ( n m × k m ) , which is greatly advantageous in communication systems. In addition, the fabrication scheme of the proposed optical fiber is practical, and its standard-compatible 42 µm core pitch promises the feasibility of integration with commercial optical networks.