Integrated Electro-Optic Frequency Comb Generation Without Resonators
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electro-optic frequency comb generators based on cascaded intensity and phase-modulators are inefficient, expensive, power-hungry, and have limited comb bandwidth, with narrow comb width and high optical insertion loss due to interconnecting discrete modulators.
Innovation Solution
An integrated on-chip frequency comb generator using a substrate with a device layer containing a series of waveguide-based electro-optic modulators, including RF electrodes shared between modulators, to generate a frequency comb efficiently, inexpensively, and with wide bandwidth.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If cascaded intensity and phase modulators are used to generate frequency combs, then comb generation capability is achieved, but device complexity and cost increase
Solution Approach 1:
The patent combines multiple discrete modulators (intensity modulator and phase modulators) into a single integrated electro-optic modulator device. This merging eliminates the need for separate modulator components and their interconnections, directly reducing device complexity while maintaining comb generation capability through unified electro-optic modulation
Solution Approach 2:
The integrated electro-optic modulator performs multiple functions simultaneously - it acts as both an intensity modulator and phase modulator within a single device structure. This multi-functionality eliminates the need for separate specialized modulators, reducing overall system complexity while achieving frequency comb generation
2Adaptability or versatility
If multiple discrete modulators are cascaded, then frequency comb generation is possible, but optical insertion loss increases
Solution Approach 1:
By merging the intensity modulation and phase modulation functions into a single integrated modulator, the patent eliminates multiple optical interfaces and interconnections between discrete modulators. This single-interface design directly reduces optical insertion loss while maintaining frequency comb generation capability
3Adaptability or versatility
If multiple phase modulators are cascaded, then comb bandwidth is expanded, but microwave driving power requirement increases
Solution Approach 1:
The integrated electro-optic modulator performs both intensity and phase modulation functions simultaneously using a single microwave drive signal. This eliminates the need for multiple separate phase modulators and their associated microwave amplifiers and phase shifters, reducing microwave driving power requirements while achieving wide comb bandwidth through the unified modulation approach
4Adaptability or versatility
If discrete modulators are interconnected through optical fibers, then frequency comb generation is achieved, but manufacturing complexity and cost increase
Solution Approach 1:
The patent integrates multiple modulator functions into a single monolithic device that can be fabricated using standard semiconductor manufacturing processes. This eliminates the need for complex assembly of discrete modulators and optical fiber interconnections, significantly simplifying manufacturing while maintaining frequency comb generation capability
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
The integrated design achieves low power consumption, wide bandwidth, and reduced optical insertion loss, enabling efficient comb generation on a compact chip with improved modulation efficiency and reduced complexity.
Implementation Method 1
The electro-optic effect is the change in the refractive index of the E/O material in the electro-optic element resulting from the application of a DC or alternating electric field. The refractive index change is caused by forces that distort the position, orientation, or shape of the molecules constituting the E/O material.
Implementation Method 2
The electric field can be created by placing a parallel plate capacitor across the crystal. Since the field inside a parallel plate capacitor depends linearly on the potential, the index of refraction depends linearly on the field, and the phase depends linearly on the index of refraction
Implementation Method 3
An integrated on-chip frequency comb generator using a substrate with a device layer containing a series of waveguide-based electro-optic modulators
Data Source
Figure 1A~1B
Figure 2A
Figure 2B
AI summary
An integrated electro-optic frequency comb generator based on ultralow loss integrated, e.g. thin-film lithium niobate, platform, which enables low power consumption comb generation spanning over a wider range of optical frequencies. The comb generator includes an intensity modulator, and at least one phase modulator, which provides a powerful technique to generate a broad high power comb, without using an optical resonator. A compact integrated electro-optic modulator based frequency comb generator, provides the benefits of integrated, e.g. lithium niobate, platform including low waveguide loss, high electro-optic modulation efficiency, small bending radius and flexible microwave design.