Inter-Mode Crosstalk Estimation between Cores for LP Modes in Weakly Coupled Few-Mode Multicore Fiber with...

Area of Science:

• Optical Fiber Communications
• Photonics
• Wave Propagation

Background:

• Inter-mode crosstalk (IMXT) is a critical challenge in few-mode multicore fibers (FM-MCFs).
• Existing models often fail under stochastic perturbations like bending and twisting.
• Understanding mode coupling is essential for designing high-performance optical fibers.

Purpose of the Study:

• To propose a novel inter-mode crosstalk (IMXT) model for few-mode multicore fiber (FM-MCF).
• To derive a universal expression for the mode coupling coefficient (MCC) considering bending and twisting.
• To enable accurate IMXT calculations using a universal semi-analytical model (USAM).

Main Methods:

• Coupled mode theory (CMT) with bending and twisting perturbations.
• Derivation of a universal mode coupling coefficient (MCC) expression.
• Application of the MCC within a universal semi-analytical model (USAM) for IMXT calculation.

Main Results:

• The proposed model shows consistency with previous theories in the absence of stochastic perturbations.
• The model effectively handles stochastic perturbations where former theories falter.
• A strong relationship between the MCC and core pitch was theoretically established.

Conclusions:

• The developed CMT-based model provides detailed physical insights into IMXT in FM-MCFs.
• The model is applicable to both homogeneous and heterogeneous FM-MCFs in phase-matching and non-phase-matching regions.
• This work broadens the applicability and accuracy of crosstalk modeling in advanced optical fibers.