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arXiv · 1402.6652

Broadband high-resolution x-ray frequency combs

Stefano M. Cavaletto·Zoltan Harman·Christian Ott·Christian Buth·Thomas Pfeifer·Christoph H. Keitel
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Abstract

Optical frequency combs have had a remarkable impact on precision spectroscopy. Enabling this technology in the x-ray domain is expected to result in wide-ranging applications, such as stringent tests of astrophysical models and quantum electrodynamics, a more sensitive search for the variability of fundamental constants, and precision studies of nuclear structure. Ultraprecise x-ray atomic clocks may also be envisaged. In this work, an x-ray pulse-shaping method is put forward to generate a comb in the absorption spectrum of an ultrashort high-frequency pulse. The method employs an optical-frequency-comb laser, manipulating the system's dipole response to imprint a comb on an excited transition with a high photon energy. The described scheme provides higher comb frequencies and requires lower optical-comb peak intensities than currently explored methods, preserves the overall width of the optical comb, and may be implemented by presently available x-ray technology.

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Stefano M. Cavaletto, Zoltan Harman, Christian Ott, Christian Buth, Thomas Pfeifer, Christoph H. Keitel. 2014-02-26. Broadband high-resolution x-ray frequency combs. https://doi.org/10.1038/nphoton.2014.113

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