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Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
High field optical nonlinearity and the Kramers-Kronig relations
J K Wahlstrand1, Y-H Cheng, H M Milchberg
1Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742, USA.
Physical Review Letters
|September 26, 2012
Summary
High laser fields induce a quadratic nonlinear optical response in noble gases like Helium and Xenon, accurately predicted by Kramers-Kronig analysis and time-dependent Schrödinger equation calculations.
Area of Science:
- Atomic and Molecular Physics
- Nonlinear Optics
- Quantum Chemistry
Background:
- Understanding the interaction of high-intensity laser fields with matter is crucial for various applications.
- Noble gas atoms are fundamental systems for studying light-matter interactions due to their simple electronic structures.
Purpose of the Study:
- To experimentally measure the nonlinear optical response of noble gas atoms (He, Ne, Ar, Kr, Xe) under high laser fields.
- To investigate the relationship between the nonlinear optical response and the laser field magnitude up to the ionization threshold.
- To validate theoretical models for predicting this response.
Main Methods:
- Absolute measurement of the nonlinear optical response.
- Utilizing Kramers-Kronig analysis with known ionization probabilities.
- Comparison with time-dependent Schrödinger equation calculations.
Main Results:
- The nonlinear optical response was found to be quadratic with respect to the laser field magnitude for all noble gases studied.
- This quadratic dependence holds true up to the ionization threshold of each respective gas.
- The experimental results show excellent agreement with predictions from Kramers-Kronig analysis and time-dependent Schrödinger equation.
Conclusions:
- The nonlinear optical response of noble gases to high laser fields is consistently quadratic below the ionization threshold.
- Kramers-Kronig relations provide a reliable method for predicting the magnitude and behavior of this response.
- Theoretical calculations, including the time-dependent Schrödinger equation, successfully model the observed phenomena.
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