A Refractive Index Sensor Based on a Metal-Insulator-Metal Waveguide-Coupled Ring Resonator.

Area of Science:

• Photonics and optical sensing
• Plasmonics
• Nanophotonics

Background:

• Refractive index sensors are crucial for various applications, including chemical and biological detection.
• Metal-insulator-metal (MIM) waveguide structures offer unique plasmonic properties for miniaturized optical devices.

Purpose of the Study:

• To design and simulate a novel refractive index sensor based on MIM waveguides and a ring resonator.
• To investigate the sensing performance and filter properties of the proposed sensor structure.
• To analyze the impact of structural parameters on the sensor's performance.

Main Methods:

• Finite-difference time-domain (FDTD) method for simulating transmission spectrum and magnetic field distribution.
• Analysis of asymmetric line shape in the transmission spectrum.
• Characterization of sensing performance using quality factor and sensitivity.

Main Results:

• The proposed sensor exhibits an asymmetric line shape in its transmission spectrum.
• The sensor demonstrates filter-like behavior, indicating potential for wavelength-selective applications.
• The study explores the relationship between structural parameters and the sensor's sensing performance and filter properties.

Conclusions:

• The developed MIM waveguide and ring resonator sensor shows promise for high-sensitivity refractive index sensing.
• The filter-like characteristics of the transmission spectrum open possibilities for integrated optical filtering.
• Further optimization of structural parameters can enhance the sensor's overall performance.