Disk-loaded silicon micro-ring resonator for high-Q resonance.

Area of Science:

• Photonics and optical engineering
• Nanotechnology and materials science

Background:

• Micro-ring resonators (MRRs) are fundamental components in integrated photonics.
• Achieving high-quality factors (Q) and specific spectral features in MRRs is crucial for advanced applications.
• Existing designs often face limitations in Q-factor, spectral control, or fabrication complexity.

Purpose of the Study:

• To introduce a novel silicon micro-ring resonator design incorporating two disks.
• To achieve ultra-high quality factors (Q) and enhanced slope rates.
• To explore the device's potential for sensing and modulation applications.

Main Methods:

• Modification of a standard silicon micro-ring resonator by adding two disks.
• Development and application of a circuit model to analyze device performance and reflections.
• Investigation of spectral features across different coupling regimes.

Main Results:

• Attainment of an asymmetric resonance with Q values up to 7.773 × 10⁵ and slope rates exceeding 880 dB/nm.
• Demonstration of three distinct operational regimes based on coupling coefficients.
• Observation of spectral discontinuities introduced by disks, offering design flexibility.
• Achieved high extinction ratio (ER) around 1550 nm.
• High sensitivity (Δλ_Res/Δn > 299 nm/RIU) demonstrated.

Conclusions:

• The proposed two-disk silicon micro-ring resonator significantly enhances Q-factor and slope rate.
• The design is compatible with standard silicon photonics technology without extra materials or steps.
• The device shows strong potential for high-performance optical sensing and modulation applications.