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arXiv · 1003.1900

Ultrafast spatio-temporal dynamics of terahertz generation by ionizing two-color femtosecond pulses in gases

I. Babushkin·W. Kuehn·C. Koehler·S. Skupin·L. Berge·K. Reimann·M. Woerner·J. Herrmann·T. Elsaesser
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Abstract

We present a combined theoretical and experimental study of spatio-temporal propagation effects in terahertz (THz) generation in gases using two-color ionizing laser pulses. The observed strong broadening of the THz spectra with increasing gas pressure reveals the prominent role of spatio-temporal reshaping and of a plasma-induced blue-shift of the pump pulses in the generation process. Results obtained from (3+1)-dimensional simulations are in good agreement with experimental findings and clarify the mechanisms responsible for THz emission.

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I. Babushkin, W. Kuehn, C. Koehler, S. Skupin, L. Berge, K. Reimann, M. Woerner, J. Herrmann, T. Elsaesser. 2010-03-09. Ultrafast spatio-temporal dynamics of terahertz generation by ionizing two-color femtosecond pulses in gases. https://doi.org/10.1103/physrevlett.105.053903

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