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arXiv · 2503.09080

Slow Light Waveguides based on Bound States in the Continuum

Yuta Tanimura·Yuki Ishii·Kenta Takata·Takahiro Uemura·Masaya Notomi·Satoshi Iwamoto·Yasutomo Ota
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Abstract

The concept of bound states in the continuum (BIC) has been advancing light confinement technology in leaky environments. In this letter, we propose and numerically demonstrate a slow light waveguide based on a BIC mode. We considered a waveguide with a polymer core loaded on a plane slab, which supports a leaky guided mode coupled to the radiation continuum in the slab. We found that periodic modulation of the polymer core along the propagation direction can result in a high group index mode with a low propagation loss due to BIC confinement. The introduction of one-dimensional photonic crystals into the BIC waveguides will largely expand its functionality and applications in integrated photonics.

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Yuta Tanimura, Yuki Ishii, Kenta Takata, Takahiro Uemura, Masaya Notomi, Satoshi Iwamoto, Yasutomo Ota. 2025-03-12. Slow Light Waveguides based on Bound States in the Continuum. https://doi.org/10.1364/ol.558273

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