Compact dual-polarization silicon integrated couplers for multicore fibers

Compact fiber-to-chip couplers play an important role in optical interconnections, especially data centers. However, the development of has been mostly limited to standard single mode fibers, with few devices compatible multicore and multimode fibers. Through use state-of-the-art optimization algorithms, we designed a compact dual-polarization coupler interface chips dense demonstrating, for first time, coupling both polarizations all cores, measured efficiency $-$4.3 dB 3 bandwidth 48 nm. The footprint 200 $\mu m^2$ per core, which makes it smallest experimentally demonstrated on silicon-on-insulator platform.