Modelocked Oscillator with Planar Gaussian Optics

Thomas Galvin | 21-LW-062

Project Overview

This project focused on developing a new architecture for integrated optical devices, including mode-locked laser oscillators. Mode-locked laser oscillators are an extremely valuable research tool, useful for spectroscopy, optical clocks, and seeding large laser chains. Mode-locked lasers based on discrete optics are bulky, expensive, and sensitive to environmental perturbations. By integrating all the components of a mode-locked laser together on a single chip using microfabrication technology, significant improvements may be realized in cost, stability, and size. In this work, we explore a new integrated architecture for integrated optical devices that can have lower loss and be easier to fabricate. The project focused on generating passive optical devices. The project created simulations, new designs tools for device layout, a fabrication process, and a test stand. The basic principle of the new architecture was demonstrated, with a propagation distance of over 100mm on a 20x30mm chip.

Mission Impact

Multiple aspects of the project will be interesting to the broader scientific community. The Planar Gaussian Optics (PGO) concept could be a new design paradigm for integrated optics. Our work in advancing this design paradigm brought us closer to creating an integrated mode-locked oscillator. Such a device could become a standard tool in chemistry, biology, and optical physics labs, both commercial and scientific. The technology is a "novel approach to improve the state of the art in detection," as called for in the detection/collection science R&D thrust in the LLNL forensic-science-mission research challenge. Because the devices could provide a stable seed to high-energy lasers, the research also contributes to the short-pulse laser R&D priority in the LLNL core competency of lasers and optical science and technology. The project supported a postdoc and trained him to use the cleanroom facilities at LLNL. He has since converted to full-time. We will be working on filing patents based on the technologies developed for this project.