IEEE Photonics Journal (Jan 2020)

Integrated Photonic 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,
  • Luis A. M. Barea,
  • Newton C. Frateschi

DOI
https://doi.org/10.1109/JPHOT.2020.3024856
Journal volume & issue
Vol. 12, no. 5
pp. 1 – 10

Abstract

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We demonstrate an integrated photonic 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 a partially unclad microdisk resonator coupled to an external clad microring resonator fabricated on silicon-on-insulator (SOI) platform. We report a RI sensitivity of 24 nm/RIU, achieving a limit of detection (LOD) of 1.7 × 10-3 refractive index units (RIU) with improved stability for an operation range of 0.15 RIU in a compact footprint of 40 × 40 μm2, representing an important solution for real-life applications in which measurement conditions are not easily controllable.

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