Overcoming fundamental noise sources in microcombs
Abstract
Microcombs enable the generation of laser frequency combs on integrated high-Q microresonators. These light sources have much larger line spacing than standard passively mode-locked laser frequency combs and offer the possibility to be massmanufactured by leveraging advances in silicon photonics. As a result, this technology is enabling new opportunities ranging from the synthesis of pure microwaves to optical clocks. The noise dynamics, such as amplification of vacuum fluctuations orthermorefractive noise in the microresonator cavity, introduce fundamental limits on the performance of these light sources in terms of optical phase noise and timing jitter. The aim of this project is to explore a radically different microcomb architecture that has the potential to overcome these limits. The key idea lies in exploring a duallocking point by self-injection locking to an external cavity. A set of experiments will be conducted to understand the fundamental limits and validate or refute the main hypotheses. We will work on dispersion-engineered ultra-high-Q silicon nitride microresonators and will consider two types of microcomb cavities, based on either one main ring or a photonic molecule arrangement (two linearly coupled cavities). The latter features much higher conversion efficiency and has radically different thermal dynamics compared to the single cavity counterpart.If successful, this project will mark a pivotal change in the field of ultrafast optics, resulting in a new class of chip-scale frequency comb sources with ultralow-timing jitter and ultrahigh-repetition rate of relevance for high-speed sampling, analog-to-digital conversion, optical frequency synthesis and the generation of pure high-frequency microwave
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 22, 2024
- Source ID
- FA86552317012
Entities
People
- Victor Torres Company
Organizations
- Air Force Office of Scientific Research
- Chalmers University of Technology
- United States Air Force