Nanorods-embedded Ring Resonator-based Plasmonic Sensor for Adulteration Detection in Honey Products

A highly sensitive plasmonic refractive index sensor using a circular ring resonator incorporating silver nanorods as defects are designed and investigated numerically in this article. The numerical investigation focuses on the impact of varying nanorod radius on the sensor’s performance. Results show that two distinct resonant dips in the transmittance spectrum are identified in the near-infrared region, where the second dip has found to have a heightened sensitivity which is particularly advantageous for chemical and biological sensing. The study reveals that increasing the nanorod radius enhances sensor sensitivity and results in a noticeable red shift in dip positions. The sensor attains a peak sensitivity of 2105 nm/RIU at nanorod radius of 22 nm. Furthermore, the proposed sensor is examined for its effectiveness in detecting adulteration in pure honey by sensing the change in resonance wavelength. The observations reveal the sensor’s capability to identify the percentage of externally introduced glucose and fructose in the honey by indicating shifts in resonance wavelength.