Open AccessHot electron dominated rapid transverse ionization growth in liquid water
Author(s) -
Michael S. Brown,
Thomas Erickson,
Kyle Frische,
W. M. Roquemore
Publication year - 2011
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.19.012241
Subject(s) - ionization , atomic physics , optics , transverse plane , electron , pulse (music) , excitation , laser , materials science , plasma , physics , ion , nuclear physics , structural engineering , quantum mechanics , detector , engineering
Pump/probe optical-transmission measurements are used to monitor in space and time the ionization of a liquid column of water following impact of an 800-nm, 45-fs pump pulse. The pump pulse strikes the 53-μm-diameter column normal to its axis with intensities up to 2 × 10(15) W/cm2. After the initial photoinization and for probe delay times < 500 fs, the neutral water surrounding the beam is rapidly ionized in the transverse direction, presumably by hot electrons with initial velocities of 0.55 times the speed of light (relativistic kinetic energy of ~100 keV). Such velocities are unusual for condensed-matter excitation at the stated laser intensities.