title: Heterogeneous trench-assisted few-mode multi-core fiber with graded-index profile and square-lattice layout for low differential mode delay.
abstract: We propose a kind of heterogeneous trench-assisted graded-index few-mode multi-core fiber with square-lattice layout. For each core in the fiber, effective area (A(eff)) of LP(01) mode and LP(11) mode can achieve about 110 μm(2) and 220 μm(2). Absolute value of differential mode delay (|DMD|) is smaller than 100 ps/km over C + L bands, which can decrease the complexity of digital signal processing at the receiver end. Considering the upper limit of cladding diameter (D(cl)) and cable cutoff wavelength of LP(21) mode in the cores located at the inner layer, we set core pitch (Λ) as 43 μm. In this case, D(cl) is about 220.4 μm, inter-core crosstalk (XT) is lower than -40 dB/500 km and the relative core multiplicity factor (RCMF) reaches 15.93.
authors.forename: Jiajing
authors.initials: J
authors.lastname: Tu
authors.forename: Kunimasa
authors.initials: K
authors.lastname: Saitoh
authors.forename: Yoshimichi
authors.initials: Y
authors.lastname: Amma
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Takenaga
authors.forename: Shoichiro
authors.initials: S
authors.lastname: Matsuo