Abstract
The ionization dynamics of free NaCl nanoparticles of 70nm mean diameter is studied in a one-color pump-probe experiment using intense near-infrared femtosecond laser pulses. We find a significant delay dependence of the electron emission yield with a pronounced maximum for optimal delays in the picosecond range. The pump-probe dynamics is interpreted by model calculations in terms of fast pump-induced metallization of the target and resonant plasmon heating of the expanding nanoplasma by the probe pulse. The picture of collective resonance absorption is supported by the observed linear scaling of the electron yield at optimal delay with probe intensity. In contrast, for pump only excitation we find a strongly nonlinear intensity dependence of the electron yield, which is attributed to the intertwining of multi-photon and tunneling ionization with non-resonant heating. Our results provide compelling evidence for the general nature and robustness of transient plasmonic resonance heating in laser-excited nanoparticles in the size regime reaching up to 100nm.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Journal of Electron Spectroscopy and Related Phenomena
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.