  Collective electron dynamics in plasmonic nanosystems can unfold on
timescales in the attosec- ond regime and the direct measurements of plasmonic
near-field oscillations is highly desirable. We report on numerical studies on
the application of attosecond nanoplasmonic streaking spectroscopy to the
measurement of collective electron dynamics in isolated Au nanospheres. The
plasmonic field oscillations are induced by a few-cycle NIR driving field and
are mapped by the energy of photoemitted electrons using a synchronized,
time-delayed attosecond XUV pulse. By a detailed analysis of the amplitudes and
phase shifts, we identify the different regimes of nanoplasmonic streaking and
study the dependence on particle size, XUV photoelectron energy and emission
position. The simulations indicate that the near-fields around the
nanoparticles can be spatio-temporally reconstructed and may give detailed
insight into the build-up and decay of collective electron motion.
