Integrated Platform for Robust Differential Refractive Index Sensor

Andre L. Moras; Valnir C. S. Junior; Mario C. M. M. Souza; Giuseppe A. Cirino; Antonio A. G. Von Zuben; Newton C. Frateschi; Luis A. M. Barea

arXiv · 1912.02853

Integrated Platform for Robust Differential Refractive Index Sensor

Andre L. Moras·Valnir C. S. Junior·Mario C. M. M. Souza·Giuseppe A. Cirino·Antonio A. G. Von Zuben·Newton C. Frateschi·Luis A. M. Barea

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Abstract

In this work, we demonstrate an integrated platform comprising a refractive index (RI) sensor based on Photonic Molecule (PM) that effectively mitigates the influence of environmental perturbations using a differential measurement scheme while providing high quality-factor (Q) resonances. The RI sensor consists of an exposed microdisk resonator coupled to an external clad microring resonator fabricated on silicon-on-insulator (SOI) platform. We report a RI sensitivity of 23 nm/RIU, achieving a limit of detection (LOD) of 1.6 x 10-3 refractive index units (RIU) with improved stability in a compact footprint of 40 x 40 μm2, representing a good solution for real-life applications in which measurement conditions are not easily controllable.

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Andre L. Moras, Valnir C. S. Junior, Mario C. M. M. Souza, Giuseppe A. Cirino, Antonio A. G. Von Zuben, Newton C. Frateschi, Luis A. M. Barea. 2019-12-05. Integrated Platform for Robust Differential Refractive Index Sensor. https://arxiv.org/abs/1912.02853

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