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arXiv · 2206.01173

Integrated Passive Nonlinear Optical Isolators

Alexander D. White·Geun Ho Ahn·Kasper Van Gasse·Ki Youl Yang·Lin Chang·John E. Bowers·Jelena Vučković
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Abstract

Fiber and bulk-optical isolators are widely used to stabilize laser cavities by preventing unwanted feedback. However, their integrated counterparts have been slow to be adopted. While several strategies for on-chip optical isolation have been realized, these rely on either integration of magneto-optic materials or high frequency modulation with acousto-optic or electro-optic modulators. Here, we demonstrate an integrated approach for passively isolating a continuous wave laser using the intrinsically non-reciprocal Kerr nonlinearity in ring resonators. Using silicon nitride as a model platform, we achieve single ring isolation of 17-23dB with 1.8-5.5dB insertion loss, and a cascaded ring isolation of 35dB with 5dB insertion loss. Employing these devices, we demonstrate hybrid integration and isolation with a semi-conductor laser chip.

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Alexander D. White, Geun Ho Ahn, Kasper Van Gasse, Ki Youl Yang, Lin Chang, John E. Bowers, Jelena Vučković. 2022-06-02. Integrated Passive Nonlinear Optical Isolators. https://doi.org/10.1038/s41566-022-01110-y

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