Gap-controlled multi-core terahertz waveguides for integration

Area of Science:

• Photonics
• Optical Communications
• Materials Science

Background:

• Single-mode fibers face limitations in data transmission capacity.
• Terahertz (THz) regime requires high-capacity solutions for chip-to-chip interconnects.
• Multi-core fibers offer increased core density and space-division multiplexing.

Purpose of the Study:

• To introduce a gap-controlled approach for modulating coupling in solid multi-core terahertz fibers.
• To demonstrate precise control over power splitting and inter-core isolation.
• To enable polarization multiplexing for enhanced channel capacity.

Main Methods:

• Analytical modeling and simulations.
• Experimental validation using 3D-printed cyclic olefin copolymer (COC) 1x3 fibers.
• Near-field scanning for visualizing evanescent coupling dynamics.

Main Results:

• Precise coupling control achieved, from -3 dB power splitting to > -35 dB inter-core isolation.
• Demonstrated suitability for high-order Quadrature Amplitude Modulation (QAM) formats.
• Rectangular core geometry enabled polarization multiplexing, doubling channel capacity.
• Monolithic design improved integration density by 280% compared to discrete fiber bundles.

Conclusions:

• The gap-controlled approach offers precise coupling modulation in THz multi-core fibers.
• This technology enhances data transmission rates and integration density for THz photonic systems.
• The developed framework is scalable for future high-density terahertz applications.