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Metal nanoplasmas as bright sources of hard x-ray pulses

P. P. Rajeev·P. Taneja·P. Ayyub·A. S. Sandhu·G. R. Kumar
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Abstract

We demonstrate a 13-fold increase in hard x-ray bremsstrahlung (10 - 200 keV) emitted by a copper plasma created by 100 fs, 806 nm pulses at $10^{14}-10^{15}$ Wcm$^{-2}$. This enhancement is achieved by roughening the target surface with copper nanoparticles of ~15 nm size. A simple model that invokes local field modifications by surface plasmon excitation and `lightning rod' effects explains the observed enhancement quantitatively and provides pointers to the design of structured surfaces for maximizing the emission.

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BibTeXRIS

P. P. Rajeev, P. Taneja, P. Ayyub, A. S. Sandhu, G. R. Kumar. 2002-11-12. Metal nanoplasmas as bright sources of hard x-ray pulses. https://doi.org/10.1103/physrevlett.90.115002

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