A. Becker et Fhm. Faisal, CORRELATED KELDYSH-FAISAL-REISS THEORY OF ABOVE-THRESHOLD DOUBLE-IONIZATION OF HE IN INTENSE LASER FIELDS, Physical review. A, 50(4), 1994, pp. 3256-3264
We have developed a correlated Keldysh-Faisal-Reiss theory of laser-in
duced double ionization of a two-electron atom. The basic N-photon T m
atrix and the expression for N-photon triple-differential rates or cro
ss sections (TDCS's) are derived. The theory is applied to investigate
the TDCS's for very-high-order multiphoton double ionization of He wi
th lasers of wavelength lambda = 248 nm and lambda = 617 nm. Compariso
n with the uncorrelated results reveals a dramatic influence of the fi
nal-state e-e correlation on the above-threshold TDCS's to be measured
in coincidence experiments in intense laser fields. The limiting case
of the TDCS's for weak-field double ionization of He by a synchroton
photon is also investigated; the results confirm the earlier theoretic
al findings and recent experimental results in that case.