Clocking plasmon nanofocusing by THz near-field streaking

Abstract

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.

4 pages, 3 figures

References in corpus (5)

• A Femtosecond Nanometer Free Electron Source
• Observation of the spin-based plasmonic effect in nanoscale structures
• Strong-field above-threshold photoemission from sharp metal tips
• Laser-induced ultrafast electron emission from a field emission tip
• Phase space manipulation of free-electron pulses from metal nanotips using combined THz near-fields and external biasing