Low-crosstalk laser-direct-writing FI/FO device for 8×100-Gbps optical interconnection

Area of Science:

• Optical engineering
• Photonics
• Telecommunications

Background:

• Weakly coupled short-reach optical interconnects using multicore fibers (MCF) require low crosstalk fan-in/fan-out (FI/FO) devices.
• Laser-direct-writing (LDW) is a key fabrication technique for these FI/FO devices.

Purpose of the Study:

• To evaluate the impact of FI/FO crosstalk on short-reach intensity-modulation/direction-detection MCF optical interconnections.
• To analyze crosstalk factors related to waveguide refractive-index profiles and misalignment in LDW-FI/FO devices.
• To develop and demonstrate low-crosstalk LDW-FI/FO devices for MCF applications.

Main Methods:

• Analysis of crosstalk in LDW-fabricated FI/FO devices considering refractive-index profiles and misalignment.
• Fabrication of compact LDW-FI/FO devices using a multiple-scan method for flat-top refractive-index profiles and aberration correction for precise alignment.
• Experimental demonstration of an 8x100-Gbps optical interconnection over 10-km MCF.

Main Results:

• Low crosstalk FI/FO devices were fabricated for 8-core MCF.
• An 8x100-Gbps optical interconnection over 10-km MCF was achieved with a low 0.5-dB penalty compared to standard single-mode fiber.
• Simulations suggest potential for transmission over 40 km.

Conclusions:

• The developed low-crosstalk LDW-FI/FO devices are suitable for high-speed optical interconnections.
• The fabricated devices significantly reduce crosstalk, enabling robust MCF-based optical links.
• This technology shows promise for extending the reach and performance of optical interconnects.