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arXiv · 2401.10508

Photonic Supercoupling in Silicon Topological Waveguides

Ridong Jia·Yi Ji Tan·Nikhil Navaratna·Abhishek Kumar·Ranjan Singh
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Abstract

Electromagnetic wave coupling between photonic systems relies on the evanescent field typically confined within a single wavelength. Extending evanescent coupling distance requires low refractive index contrast and perfect momentum matching for achieving a large coupling ratio. Here, we report the discovery of photonic supercoupling in a topological valley Hall pair of waveguides, showing a substantial improvement in coupling efficiency across multiple wavelengths. Experimentally, we realize ultra-high coupling ratios between waveguides through valley-conserved vortex flow of electromagnetic energy, attaining 95% coupling efficiency for separations of up to three wavelengths. This demonstration of photonic supercoupling in topological systems significantly extends the coupling distance between on-chip waveguides and components, paving the path for the development of supercoupled photonic integrated devices, optical sensing, and telecommunications.

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physics.opticscond-mat.mes-hallcond-mat.mtrl-sciphysics.app-phquant-ph

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Ridong Jia, Yi Ji Tan, Nikhil Navaratna, Abhishek Kumar, Ranjan Singh. 2024-01-19. Photonic Supercoupling in Silicon Topological Waveguides. https://arxiv.org/abs/2401.10508

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