Engineer with thousands of fabricated devices pours cold water on photonic crystal modulator yields
jwt0625 · x · 2026-10-26
A practitioner who has fabricated thousands of such devices critiques the photonic crystal modulator paper: these devices are extremely hard to make consistent, requiring geometry scaling of a few percent across the chip so some fall within a Santec tunable laser's 100nm range, plus annoying precompensation. He argues the paper ignores yield and per-bit thermal tuning energy, making it not worth the hassle vs. MRMs (radius <10 μm), which are also far smaller. He adds it's Baba's slow-light approach, working near the photonic crystal bandgap—prone to random localization and bad spectra.
Related event: Photonic Crystal Modulator Hits 200G/Channel, But Engineers Question Yield(2 posts)→
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