High-energy cutoff in the spectrum of strong-field nonsequential double ionization.
Electron energy distributions of singly and doubly ionized helium in an intense 390 nm laser field have been measured at two intensities (0.8 PW/cm2 and 1.1 PW/cm2, where PW is defined as 10(15) W/cm2). Numerical solutions of the full-dimensional time-dependent helium Schrödinger equation show excellent agreement with the experimental measurements. The high-energy portion of the two-electron energy distributions reveals an unexpected 5U(p) cutoff for the double ionization (DI) process and leads to a proposed model for DI below the quasiclassical threshold.
Parker
J S
JS
DAMTP, Queen's University Belfast, Belfast, BT7 1NN, United Kingdom.
Doherty
B J S
BJ
Taylor
K T
KT
Schultz
K D
KD
Blaga
C I
CI
DiMauro
L F
LF