Analytical expressions for Z-scan with arbitrary phase change in thin nonlocal nonlinear media

Area of Science:

• Nonlinear Optics
• Materials Science

Background:

• Understanding light-matter interactions in materials with nonlinear optical properties is crucial for developing advanced optical devices.
• Simultaneous changes in refractive index and absorption (nonlinear refraction and absorption) present complex phenomena that are challenging to model analytically.

Purpose of the Study:

• To derive analytical expressions for the normalized transmittance of thin materials exhibiting simultaneous nonlocal nonlinear changes in refraction and absorption.
• To develop formulas applicable to any magnitude of nonlinear optical effects.
• To compare nonlocal and local nonlinear optical models and validate the derived expressions against experimental data.

Main Methods:

• Utilized the Gaussian decomposition method to derive analytical expressions.
• Developed formulas capable of handling arbitrary magnitudes of nonlinear refractive index and absorption changes.
• Performed comparative analysis between nonlocal and local nonlinear optical scenarios.
• Validated the theoretical expressions by fitting them to experimental results.

Main Results:

• Derived analytical expressions for normalized transmittance under simultaneous nonlocal nonlinear refraction and absorption.
• The developed formulas are valid for all magnitudes of nonlinear changes.
• Demonstrated the differences between nonlocal and local nonlinear optical effects.
• Achieved excellent agreement between the derived expressions and experimental data.

Conclusions:

• The derived analytical expressions provide an accurate and versatile tool for analyzing light propagation in materials with simultaneous nonlocal nonlinear optical effects.
• The Gaussian decomposition method is effective for modeling complex nonlinear optical phenomena.
• The findings contribute to a better understanding and prediction of material behavior in nonlinear optical applications.