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Clocking plasmon nanofocusing by THz near-field streaking

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 نشر من قبل Benjamin Schr\\\"oder
 تاريخ النشر 2020
  مجال البحث فيزياء
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We apply terahertz (THz) near-field streaking in a nanofocusing geometry to investigate plasmon polariton propagation on the shaft of a conical nanotip. By evaluating the delay between a streaking spectrogram for plasmon-induced photoemission with a measurement for direct apex excitation, we obtain an average plasmon group velocity, which is in agreement with numerical simulations. Combining plasmon-induced photoemission with THz near-field streaking facilitates extensive control over localized photoelectron sources for time-resolved imaging and diffraction.



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