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arXiv · 1903.00573

Beam Distortion Effects upon focusing an ultrashort Petawatt Laser Pulse to greater than 10$^{22}$ W/cm$^{2}$

Ganesh Tiwari·Erhard Gaul·Mikael Martinez·Gilliss Dyer·Joseph Gordon·Michael Spinks·Toma Toncian·Brant Bowers·Xuejing Jiao·Rotem Kupfer·Luc Lisi·Edward Mccary·Rebecca Roycroft·Andrew Yandow·Griffin Glenn·Mike Donovan·Todd Ditmire·Bjorn Manuel Hegelich
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Abstract

When an ultrashort laser pulse is tightly focused to a size approaching its central wavelength, the properties of the focused spot diverge from the diffraction limited case. Here we report on this change in behavior of a tightly focused Petawatt class laser beam by an F/1 off-axis paraboloid (OAP). Considering the effects of residual aberration, the spatial profile of the near field and pointing error, we estimate the deviation in peak intensities of the focused spot from the ideal case. We verify that the estimated peak intensity values are within an acceptable error range of the measured values. With the added uncertainties in target alignment, we extend the estimation to infer on-target peak intensities of $\geq$ 10$^{22}$ W/cm$^{2}$ for a target at the focal plane of this F/1 OAP.

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Ganesh Tiwari, Erhard Gaul, Mikael Martinez, Gilliss Dyer, Joseph Gordon, Michael Spinks, Toma Toncian, Brant Bowers, Xuejing Jiao, Rotem Kupfer, Luc Lisi, Edward Mccary, Rebecca Roycroft, Andrew Yandow, Griffin Glenn, Mike Donovan, Todd Ditmire, Bjorn Manuel Hegelich. 2019-03-01. Beam Distortion Effects upon focusing an ultrashort Petawatt Laser Pulse to greater than 10$^{22}$ W/cm$^{2}$. https://doi.org/10.1364/ol.44.002764

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