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Published on: February 27, 2019
Application of classical models of chirality to optical rectification
Xiao-Ou Wang1, Li-Jing Gong, Chun-Fei Li
1Department of Physics, Harbin Institute of Technology, Harbin 15000, People's Republic of China. wxo@hit.edu.cn
The Journal of Chemical Physics
|December 3, 2008
Summary
This study reveals that optical rectification in chiral media arises from the interaction between electric field gradients and chiral molecules. This finding clarifies the microscopic origins of this nonlinear optical effect.
Area of Science:
- Nonlinear Optics
- Molecular Chirality
- Condensed Matter Physics
Background:
- Chirality is a fundamental property in molecular systems with significant optical implications.
- Optical rectification, a second-order nonlinear optical phenomenon, generates a DC current from an AC optical field.
- Understanding its mechanism in chiral media is crucial for developing novel optical devices.
Purpose of the Study:
- To investigate the optical rectification effect in chiral molecular media using classical models.
- To theoretically derive the nonlinear optical susceptibilities responsible for this effect.
- To elucidate the microscopic mechanism underlying optical rectification in chiral systems.
Main Methods:
- Classical models of chirality were employed.
- Calculations of zero-frequency first hyperpolarizabilities for various chiral molecules were performed.
- Theoretical derivation of second-order nonlinear static-electric-dipole susceptibilities in isotropic chiral thin films was conducted.
Main Results:
- A DC electric-dipole polarization was derived from the calculated hyperpolarizabilities.
- Expressions for second-order nonlinear static-electric-dipole susceptibilities were obtained.
- The analysis identified the interaction between electric field gradients (spatial dispersion) and chiral molecules as the source of optical rectification.
Conclusions:
- Optical rectification in chiral media is fundamentally linked to spatial dispersion effects.
- The derived theoretical framework is consistent with previous findings, emphasizing the role of fourth-order electric-dipole susceptibilities.
- This research provides a deeper understanding of nonlinear optical phenomena in chiral materials.
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