Quasi-phase matched second harmonic generation in a PMN-38PT crystal

Area of Science:

• Materials Science
• Nonlinear Optics
• Crystallography

Background:

• Lead magnesium niobate-lead titanate (PMN-38PT) is a ferroelectric crystal with significant potential for nonlinear optical applications.
• Fabricating high-quality nonlinear gratings is crucial for efficient nonlinear optical devices.
• Accurate characterization of nonlinear optical coefficients is essential for material development and device design.

Purpose of the Study:

• To fabricate quadratic nonlinearity gratings in PMN-38PT crystals using an all-optical poling method.
• To quantitatively determine all three non-zero quadratic nonlinearity coefficients of the PMN-38PT crystal.
• To demonstrate the utility of these gratings in quasi-phase matched second harmonic generation.

Main Methods:

• All-optical poling was employed to create gratings within the PMN-38PT crystal.
• Quasi-phase matched collinear second harmonic generation (SHG) was utilized.
• Second harmonic output measurements were performed to derive nonlinear coefficients.

Main Results:

• Quadratic nonlinearity gratings were successfully fabricated in the PMN-38PT crystal.
• Quantitative estimates for all three independent nonlinear quadratic coefficients (d11, d13, d33) were obtained.
• The study provides the first comprehensive dataset of these coefficients for PMN-38PT.

Conclusions:

• All-optical poling is an effective method for creating nonlinear gratings in PMN-38PT.
• The determined nonlinear coefficients offer valuable data for future applications of PMN-38PT in nonlinear optics.
• This work establishes a foundation for precise characterization of nonlinear optical properties in ferroelectric crystals.