Exact Keldysh theory of strong-field ionization: Residue method versus saddle-point approximation

@article{Vanne2007ExactKT,
  title={Exact Keldysh theory of strong-field ionization: Residue method versus saddle-point approximation},
  author={Yulian V. Vanne and Alejandro Saenz},
  journal={Physical Review A},
  year={2007},
  volume={75},
  pages={033403}
}
In recent articles [K. Mishima et al., Phys. Rev. A, 66, 033401 (2002); S. D. Chao, Phys. Rev. A, 72, 053414 (2005)] it was proposed to use the residue theorem for the exact calculation of the transition amplitude describing strong-field ionization of atomic systems within Keldysh theory. This should avoid the necessity of applying the method of steepest descent (saddle-point approximation). Comparing the results of both approaches for atomic hydrogen a difference by a factor of 2 was found for… 
Keldysh theory re-examined
A derivation of the ionization rate for a hydrogen atom in its ground state (or a hydrogen-like positive ion) in a strong linearly polarized laser field is presented. The derivation utilizes the
Higher order expansion of Keldysh integral for hydrogen atom and molecular ion
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
Colloquium: Strong-field phenomena in periodic systems
The advent of visible-infrared laser pulses carrying a substantial fraction of their energy in a single field oscillation cycle has opened a new era in the experimental investigation of ultrafast
Keldysh theory of strong-field ionization
In this paper, we provide a detailed derivation of the strong-field ionization rates originally developed by Keldysh who introduced the strong-field approximation. Numerical results are presented t...
Theoretical Foundations of Femtosecond Filamentation
In the following chapter, the theoretical modeling of femtosecond filamentation is discussed. For a detailed understanding of this phenomenon, the dynamical equation governing the evolution of the