Ultrafast laser-induced anisotropic structural dynamics of five-fold twinned silver nanowires

Ultrafast transmission electron microscopy, a powerful tool for visualizing ultrafast structural dynamics, is harnessed here to reveal the full-cycle reversible dynamics of five-fold twinned silver nanowires across picosecond to microsecond timescales. On the picosecond timescale, a two-step process was identified: a fast electron-phonon coupling step and a slower step ascribed to hot electron decay due to trap states. Anisotropic phonon-phonon interactions, arising from the one-dimensional structure of the silver nanowires, drive energy transfer from the radial to the axial direction on the nanosecond scale. The subsequent recovery of the lattice occurs on the microsecond scale. These findings pave the way for advanced ultrafast device applications.