Simultaneous type I and type II Čerenkov-phase matched second-harmonic generation in disordered nonlinear photonic...

Area of Science:

• Nonlinear optics
• Photonics
• Materials science

Background:

• Čerenkov-phase matched second-harmonic generation (SHG) is crucial for frequency conversion.
• Disordered nonlinear photonic crystals offer unique light manipulation properties.
• Controlling SHG in disordered structures presents significant challenges.

Purpose of the Study:

• To investigate simultaneous type I and II Čerenkov-phase matched SHG.
• To explore the impact of domain and beam width scaling on SHG.
• To analyze the polarization, emission angles, and intensities of the generated light.

Main Methods:

• Fabrication and characterization of disordered nonlinear photonic crystals.
• Experimental setup for observing simultaneous type I and II SHG.
• Systematic variation of ferroelectric domain width and laser beam width.
• Analysis of polarization, emission angles, and intensity spectra.

Main Results:

• Successful observation of simultaneous type I and II Čerenkov-phase matched SHG.
• Demonstration that matching domain and beam widths enhances SHG.
• Detailed analysis of polarization-dependent emission and angular distributions.
• Correlation between domain width, beam width, and SHG intensity.

Conclusions:

• Disordered nonlinear photonic crystals can support simultaneous type I and II SHG.
• Precise control over structural parameters enables efficient frequency conversion.
• The findings provide insights into light propagation and nonlinear interactions in disordered media.