Design and analysis of ultra-large capacity heterogeneous nineteen-core seven-mode fiber

Abstract

The multi-core few-mode fiber based on space division multiplexing technology is one of the critical ways to address the issue that the current single-mode fiber communication capacity has reached its maximum. However, the energy crosstalk between the cores is an important reason for the deterioration of signal quality. Consequently, this paper designs a nineteen-core seven-mode fiber with more transmission channels, and the auxiliary structures such as trench, high and low refractive index double rings, and air holes can effectively reduce intra-core crosstalk and inter-core crosstalk. After optimization, each core of the nineteen-core fiber can transmit seven LP modes, and the effective refractive index difference between adjacent modes is greater than or equal to 10−3. The optical fiber provides 228 transmission channels for the entire transmission system, the inter-core crosstalk of the highest order LP41 mode is lower than −30 dB/100 km at 1550 nm. Based on the above, the proposed optical fiber has excellent optical properties and can be applied to data centers, optical sensors, high-speed computer communication networks, and other applications.