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arXiv · 1905.00098

Photon Acceleration in a Flying Focus

A. J. Howard·D. Turnbull·A. S. Davies·P. Franke·D. H. Froula·J. P. Palastro
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Abstract

A high-intensity laser pulse propagating through a medium triggers an ionization front that can accelerate and frequency-upshift the photons of a second pulse. The maximum upshift is ultimately limited by the accelerated photons outpacing the ionization front or the ionizing pulse refracting from the plasma. Here we apply the flying focus--a moving focal point resulting from a chirped laser pulse focused by a chromatic lens--to overcome these limitations. Theory and simulations demonstrate that the ionization front produced by a flying focus can frequency-upshift an ultrashort optical pulse to the extreme ultraviolet over a centimeter of propagation. An analytic model of the upshift predicts that this scheme could be scaled to a novel table-top source of spatially coherent x-rays.

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BibTeXRIS

A. J. Howard, D. Turnbull, A. S. Davies, P. Franke, D. H. Froula, J. P. Palastro. 2019-04-30. Photon Acceleration in a Flying Focus. https://doi.org/10.1103/physrevlett.123.124801

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