Design of Heterogeneous 4LP-Mode Multicore Fiber with Two-Ring Layout

Heterogeneous 4LP-mode 4- and 6-core fibers with a
$125-\mu \mathrm{m}$
cladding diameter are investigated. We optimize core parameters with a two-ring layout to increase the spatial channel count (SCC) with low crosstalk (XT). Numerical results show that by extending the number of modes from 2LP-mode to 4LP-mode, the SCC of the 6-core fiber is increased from 18 to 36 with keeping the XT value similar. Also, the XT of the 4LP-mode 4-core fiber (4LP-4CF) is significantly reduced to -91 dB@1km compared with that of the 2LP-8CF (-35 dB@1km), which has the same SCC of 24.