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arXiv · 1810.08834

Boosting terahertz-radiation power with two-color circularly polarized midinfrared laser pulses

V. A. Tulsky·M. Baghery·U. Saalmann·S. V. Popruzhenko
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Abstract

A way to considerably enhance terahertz radiation, emitted in the interaction of intense mid-infrared laser pulses with atomic gases, in both the total energy and the electric-field amplitude is suggested. The scheme is based on the application of a two-color field consisting of a strong circularly polarized mid-infrared pulse with wavelengths of $1.6\div 4\,\mu{\rm m}$ and its linearly or circularly polarized second harmonic of lower intensity. By combining the strong-field approximation for the ionization of a single atom with particle-in-cell simulations of the collective dynamics of the generated plasma it is shown that the application of such two-color circularly polarized laser pulses may lead to an order-of-magnitude increase in the energy emitted in the terahertz frequency domain as well as in a considerable enhancement in the maximal electric field of the terahertz pulse. Our results support recently reported experimental and numerical findings.

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V. A. Tulsky, M. Baghery, U. Saalmann, S. V. Popruzhenko. 2018-10-20. Boosting terahertz-radiation power with two-color circularly polarized midinfrared laser pulses. https://doi.org/10.1103/physreva.98.053415

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