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arXiv · 1606.01931

High harmonic interferometry of the Lorentz force in strong mid-infrared laser fields

Emilio Pisanty·Daniel D. Hickstein·Benjamin R. Galloway·Charles G. Durfee·Henry C. Kapteyn·Margaret M. Murnane·Misha Ivanov
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Abstract

The interaction of intense mid-infrared laser fields with atoms and molecules leads to a range of new opportunities, from the production of bright, coherent radiation in the soft x-ray range to imaging molecular structures and dynamics with attosecond temporal and sub-angstrom spatial resolution. However, all these effects, which rely on laser-driven recollision of an electron removed by the strong laser field and the parent ion, suffer from the rapidly increasing role of the magnetic field component of the driving pulse: the associated Lorentz force pushes the electrons off course in their excursion and suppresses all recollision-based processes, including high harmonic generation, elastic and inelastic scattering. Here we show how the use of two non-collinear beams with opposite circular polarizations produces a forwards ellipticity which can be used to monitor, control, and cancel the effect of the Lorentz force. This arrangement can thus be used to re-enable recollision-based phenomena in regimes beyond the long-wavelength breakdown of the dipole approximation, and it can be used to observe this breakdown in high-harmonic generation using currently-available light sources.

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Emilio Pisanty, Daniel D. Hickstein, Benjamin R. Galloway, Charles G. Durfee, Henry C. Kapteyn, Margaret M. Murnane, Misha Ivanov. 2016-06-06. High harmonic interferometry of the Lorentz force in strong mid-infrared laser fields. https://doi.org/10.1088/1367-2630/aabb4d

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