Dual-comb spectroscopy in the deep ultraviolet
John J. McCauley, Mark C. Phillips, Reagan R. D. Weeks, Yu Zhang, S. S. Harilal, R. Jason Jones
Abstract
This Letter reports dual-frequency-comb spectroscopy in the deep ultraviolet used to characterize transient laser-produced plasmas. Dual-comb spectroscopy at these wavelengths enables access to a large number of strong electronic transitions in neutral and ionized atoms and molecules. This broadband dual-frequency-comb system at 265 nm measures multiple transitions in neutral and singly ionized iron atoms in a laser-produced plasma. Analysis of absorption spectra yields time-resolved ion and neutral column densities, excitation temperatures, and electron densities, which are measured down to 10 14 cm −3 levels. The results provide insights into low-temperature plasma properties.