Higher order expansion of Keldysh integral for hydrogen atom and H-2(+) molecular ion

作者：Long Zi Jian^*; Liu Wing Ki

来源：Journal of Modern Optics, 2011, 58(13): 1141-1148.

DOI：10.1080/09500340.2011.582962

• strong field ionisation
• asymptotic expansion
• molecular ion
• residue theorem
• LCAO
• saddle point
• method of steepest descent

In this paper we provide a systematic method of finding the higher order asymptotic expansion of the Keldysh integral using the hydrogen atom as an example. Comparisons with exact numerical integration shows that the second-order correction improves the the first-order results significantly. We extend this method to molecular ionisation in H-2(+) and calculate the total ionisation rate. The results are in good agreement with the exact solution of the time-dependent Schrodinger equation.

• 出版日期2011