A Review of Photonic Sensors Based on Ring Resonator Structures: Three Widely Used Platforms and Implications of Sensing Applications

Abstract

Optical ring resonators (RRs) are a novel sensing device that has recently been developed for several sensing applications. In this review, RR structures based on three widely explored platforms, namely silicon-on-insulator (SOI), polymers, and plasmonics, are reviewed. The adaptability of these platforms allows for compatibility with different fabrication processes and integration with other photonic components, providing flexibility in designing and implementing various photonic devices and systems. Optical RRs are typically small, making them suitable for integration into compact photonic circuits. Their compactness allows for high device density and integration with other optical components, enabling complex and multifunctional photonic systems. RR devices realized on the plasmonic platform are highly attractive, as they offer extremely high sensitivity and a small footprint. However, the biggest challenge to overcome is the high fabrication demand related to such nanoscale devices, which limits their commercialization.

Dielectric Waveguide-Based Sensors with Enhanced Evanescent Field: Unveiling the Dynamic Interaction with the Ambient Medium for Biosensing and Gas-Sensing Applications—A Review

“…The landscape of materials employed in integrated optics has evolved significantly, driven by the emergence of innovative materials such as SiO 2 , LiNbO 3 , SOI, GaAs, InP, and organic polymers [10,40]. SOI-based optical WG systems boast several advantages, including a substantial refractive index difference, minimal transmission loss, and a high degree of integration capability.…”

“…The mode coupling theory, applicable to sensors like surface plasmon resonance (SPR) and grating sensors, is employed to calculate the resultant change in the effective refractive index [7][8][9]. This calculation method extends to devices such as microring resonators (MRRs) [10,11], Mach-Zehnder interferometers (MZIs) [12], multimode interferences (MMIs) [13,14], fiber Bragg gratings [15], photonic crystals [16], and other differential interferometers [17].…”

Integrated Photonic Passive Building Blocks on Silicon-on-Insulator Platform

“…Consequently, RRs play a pivotal role in quantum computing. In 2023, Kazanskiy et al [162] explored various applications, including biomedical sensing, environmental monitoring, and chemical analysis, focusing solely on RRs in the SOI platform. However, it is worth noting that the same structure can also be implemented on plasmonic and polymer platforms.…”

A Concise Review of the Progress in Photonic Sensing Devices

“…Choosing the right substrate is crucial for plasmonic sensors [19]. The substrate should be optically transparent in the spectral range of interest to enable efficient coupling of light with the plasmonic structures [81]. Additionally, the substrate should have low autofluorescence and minimal interaction with the analyte being sensed.…”