Executive Summary : | Nonlinear frequency generation in optical fibers has revolutionized various applications, including optical frequency metrology and biomedical imaging. However, much of the research has focused on novel materials and systems for generating new optical frequencies, neglecting fundamental aspects like intensity and phase noise properties. A typical nonlinear frequency generation in optical fibers involves a pump laser and an optical fiber, with the time and spectral domain properties of the pump laser playing a crucial role in the noise properties of the newly generated frequencies. Understanding and controlling these noise properties is crucial for critical applications like gravitational wave detection, quantum optics, optical magnetometry, and early-stage pathology detection in medical imaging. The objective of this proposal is to develop experimental and numerical methods for systematic study of the effects of pump laser properties, architectures, and nonlinear system parameters on Stimulated Raman scattering and Supercontinuum generation. In-house multiple fiber laser architectures will be developed to provide different time and spectral domain pump laser signals, and these will be used for nonlinear frequency generation in multiple step-index optical fibers. Numerical simulations will be conducted to optimize the noise performance of both pump laser systems and nonlinear optical frequency generation processes. The research will demonstrate experimental testbeds for low noise nonlinear frequency generation processes, providing the recipe of pump wavelength, temporal and spectral characteristics, and architecture for generating nonlinear optical frequencies with noise properties that satisfy critical application performance demands. This research has two impacts: disseminating new knowledge about nonlinear optical physics in fibers and enabling disruptive fiber-based source technologies for existing and future critical applications. |