1.2 Pb/s throughput transmission using a 160 μm cladding, 4-core, 3-mode fiber

This paper extends a recent demonstration of 1.2 Pb/s transmission using a few-mode multi-core fiber with a cladding diameter of 160 μm. The fiber was a 3.37 km, 4-core, 3-mode few-mode multi-core fiber with spatial multiplexing and demultiplexing performed with especially designed mode-selective couplers. We transmitted 368 wavelength division multiplexed spatial super channels across the C and L bands. We selected polarization-division-multiplexed-256-quadrature amplitude modulation format to maximize the generalized mutual information of the transmitted signals, which were decoded using punctured soft-decision forward error correction with a code rate granularity of 0.01. The maximum crosstalk of the system was-31 dB between LP₁₁ modes of adjacent cores, leading to a Q-factor penalty of approximately 0.5 dB. We estimated the system mode-dependent loss values ranging from 3 dB to 5 dB across C and L bands with negligible wavelength dependence.