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arXiv · 1911.04990

Absolute measurement of laser ionization yield in atmospheric pressure range gases over 14 decades

D. Woodbury·R. M. Schwartz·E. Rockafellow·J. K. Wahlstrand·H. M. Milchberg
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Abstract

Strong-field ionization is central to intense laser-matter interactions. However, standard ionization measurements have been limited to extremely low density gas samples, ignoring potential high density effects. Here, we measure strong-field ionization in atmospheric pressure range air, N2 and Ar over 14 decades of absolute yield, using mid-IR picosecond avalanche multiplication of single electrons. Our results are consistent with theoretical rates for isolated atoms and molecules and quantify the ubiquitous presence of ultra-low concentration gas contaminants that can significantly affect laser-gas interactions.

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D. Woodbury, R. M. Schwartz, E. Rockafellow, J. K. Wahlstrand, H. M. Milchberg. 2019-11-06. Absolute measurement of laser ionization yield in atmospheric pressure range gases over 14 decades. https://doi.org/10.1103/physrevlett.124.013201

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