论文部分内容阅读
So far, nonsequential double ionization (NSDI) of atoms can be well understood within a semiclassical or even classical picture.No quantum effect appears to be required to explain the data observed.We theoretically study electron correlation resulting from NSDI of argon in a low-intensity laser field using a quantum-mechanical S-matrix theory.We show that quantum interference between the contributions of different intermediate excited states of the singly charged argon ion produces a transition from back-to-back to side-by-side emission with increasing laser intensity, which is in close agreement with the experimental data.For higher intensities, this transition is enhanced by the consequences of depletion of the excited states.