XUV Frequency Combs for Precision Spectroscopy

University Of Arizona, Tucson AZ

Investigators

Abstract

This project will utilize precision frequency comb spectroscopy in the vacuum-ultraviolet (VUV) and extreme ultraviolet (XUV) to investigate atomic and molecular transitions that have significant value in increasing our understanding of fundamental physics. A new method utilizing two phase-coherent XUV femtosecond frequency combs will be investigated as a promising path towards high-resolution spectroscopy with unprecedented accuracy in this difficult to reach spectral region. The physics to be explored in this project will come from two distinct objectives: (1) to elucidate how the physics underlying intracavity high harmonic generation affects the conversion efficiency and noise characteristics of the XUV femtosecond frequency comb, and (2) to utilize the dual-XUV frequency comb approach to provide an improved measurement of high-n Rydberg states (n~50-60) in molecular hydrogen, thereby providing an improved value for the ionization and dissociation energy of this physically important molecular system. This program will provide a unique research-based education for graduate students in the fundamentals of light-matter interaction, advanced laser systems, and their use to probe and better understand the most basic and common molecule: molecular hydrogen. Some of the most basic atomic and molecular systems have their first resonance in the vacuum-ultraviolet portion of the light spectrum. This is a region where few laser sources exist, making it difficult to precisely study the structure of atoms and molecules needed for testing our understanding of current physical models. This program will utilize recently developed sources and techniques to study molecular hydrogen with much greater precision, and open the door to further studies in this difficult to reach spectral region. Such research provides a solid foundation to prepare the next generation of scientists to serve in our national, academic, and industrial research laboratories.