Optical Ring Resonator Waveguide Width Variation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Mechanical and electrical contacts to microring resonators perturb the resonant modes of light, leading to significant propagation losses and a reduced quality factor (Q), limiting their utility in applications requiring high Q for narrowband filtering, switching, or modulation.
Innovation Solution
The development of optical ring resonator devices with non-uniform width optical waveguide rings, where mechanical and electrical contacts are made from inside the resonator near the maximum width, allowing for the integration of electrical heaters or semiconductor junctions without perturbing the resonant modes, and enabling high Q preservation and small resonator size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If mechanical and electrical contacts are made to the microring resonator, then electrical connections and tuning capability are achieved, but the resonant modes of light are perturbed and propagation losses increase
Solution Approach 1:
The waveguide ring is designed with non-uniform width where the width varies along the circumference. The maximum width region is specifically positioned at the contact location to minimize perturbation of resonant modes, while other regions have different widths optimized for their specific functions. This local variation in geometry allows electrical contacts to be made without significantly affecting the overall resonant characteristics.
Solution Approach 2:
The waveguide ring is pre-designed with a non-uniform width profile before making electrical contacts. By anticipating the need for electrical connections, the maximum width region is strategically positioned at the contact location in advance, ensuring that when contacts are made, the perturbation to resonant modes is minimized from the outset.
2Volume of moving object
If the microring resonator size is reduced, then the free-spectral range increases, but maintaining high Q becomes more difficult due to contact perturbations
Solution Approach 1:
By creating regions of different widths in the waveguide ring, the design allows small overall dimensions while protecting the resonant modes from contact perturbations. The maximum width region at the contact point acts as a buffer that minimizes the impact of electrical contacts on the resonant modes, enabling small resonator size to be maintained without sacrificing Q factor.
3Ease of manufacture
If uniform width is used in the optical waveguide ring, then manufacturing is simplified, but electrical contacts perturb the resonant modes and reduce Q
Solution Approach 1:
The waveguide ring employs non-uniform width with specific regions optimized for different functions. The maximum width region is positioned at the electrical contact location to minimize perturbation, while other regions have widths optimized for light propagation and resonant mode confinement. This localized variation in geometry maintains high Q factor despite the added manufacturing complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach minimizes transmission loss and maintains a high quality factor, enabling efficient optical signal routing, switching, and filtering while allowing for mechanical and thermal isolation, and enabling resonant frequency tuning.
Implementation Method 1
an optical waveguide ring in the optical ring resonator device can have a non-uniform width which adiabatically varies between a maximum value and a minimum value
Implementation Method 2
either an electrical heater or a semiconductor junction to be located inside the optical waveguide ring for use in varying (i.e. tuning) a resonant frequency therein
Implementation Method 3
an optical waveguide located near the optical waveguide ring at a location proximate to the minimum value of the width of the optical waveguide ring to couple light between the optical waveguide and the optical waveguide ring
Data Source
AI summary
Optical ring resonator devices are disclosed that can be used for optical filtering, modulation or switching, or for use as photodetectors or sensors. These devices can be formed as microdisk ring resonators, or as open-ring resonators with an optical waveguide having a width that varies adiabatically. Electrical and mechanical connections to the open-ring resonators are made near a maximum width of the optical waveguide to minimize losses and thereby provide a high resonator Q. The ring resonators can be tuned using an integral electrical heater, or an integral semiconductor junction.