Photon Acceleration in a Flying Focus

Journal Article · 20 September 2019 · Physical Review Letters

DOI: https://doi.org/10.1103/PhysRevLett.123.124801 · OSTI ID:1566142

Howard, A. J. ^[1]; Turnbull, D. ^[1]; Davies, A. S. ^[1]; Franke, P. ^[1]; Froula, D. H. ^[1]; Palastro, J. P. ^[1]

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1. Univ. of Rochester, Rochester, NY (United States). Lab for Laser Energetics

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. Here, 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.

• Research Organization: Univ. of Rochester, Rochester, NY (United States). Lab for Laser Energetics
• Sponsoring Organization: USDOE Office of Science (SC), Fusion Energy Sciences (FES); USDOE National Nuclear Security Administration (NNSA)
• Contributing Organization: Laboratory for Laser Energetics, University of Rochester
• Grant/Contract Number: NA0001944
• OSTI ID: 1566142
• Report Number(s): 2019-46, 2477, 1517; PRLTAO; 2019-46, 2477, 1517; TRN: US2000948
• Journal Information: Physical Review Letters, Vol. 123, Issue 12; ISSN 0031-9007
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English