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Bound electron nonlinearity beyond the ionization threshold



Jared K. Wahlstrand, Sina Zahedpour, Anand Bahl, Miroslav Kolesik, H M. Milchberg


Although high field laser-induced ionization is a fundamental process at the root of many applications, there have been no absolute measurements of its transient rate. Such information is crucial, for example, for understanding the propagation of high intensity ultrashort pulses in matter. Here, we present absolute space- and time-resolved measurements of the ultrafast laser-driven ionization in argon, krypton, xenon, nitrogen up to an ionization fraction of about 1%. These accurate measurements of the ionization rate directly enable determination of the non-perturbative bound electron nonlinearity well beyond the ionization threshold, where it is found to be approximately linear in intensity through >100 TW/cm2.
Physical Review Letters


field ionization, spectral interferometry, atomic physics, ultrafast optics


Wahlstrand, J. , Zahedpour, S. , Bahl, A. , Kolesik, M. and Milchberg, H. (2018), Bound electron nonlinearity beyond the ionization threshold, Physical Review Letters, [online], (Accessed April 14, 2024)
Created May 2, 2018, Updated November 10, 2018