Nonsequential two-photon absorption from the K shell in solid zirconium

Authors

• Shambhu Ghimire, SLAC National Accelerator Laboratory
• Matthias Fuchs, University of Nebraska - LincolnFollow
• Jerry Hastings, SLAC National Accelerator Laboratory
• Sven C. Hermann, SLAC National Accelerator Laboratory
• Yuichi Inubushi, RIKEN SPring-8 Center
• Jack Pines, SLAC National Accelerator Laboratory
• Sharon Shwartz, Bar Ilan University
• Makina Yabashi, SLAC National Accelerator Laboratory
• David A. Reis, SLAC National Accelerator Laboratory

Document Type

Article

Date of this Version

2016

Citation

PHYSICAL REVIEW A 94, 043418 (2016)

Comments

©2016 American Physical Society

Abstract

We report the observation of nonsequential two-photon absorption from the K shell of solid Zr (atomic number Z = 40) using intense x-ray pulses from the Spring-8 Angstrom Compact Free-Electron Laser (SACLA). We determine the generalized nonlinear two-photon absorption cross section at the two-photon threshold in the range of 3.9–57 ×10⁻⁶⁰ cm⁴ s bounded by the estimated uncertainty in the absolute intensity. The lower limit is consistent with the prediction of 3.1 ×10⁻⁶⁰ cm⁴ s from the nonresonant Z⁻⁶ scaling for hydrogenic ions in the nonrelativistic, dipole limit.