Loss in solid-core photonic crystal fibers due to interface roughness scattering

Area of Science:

• Optics and Photonics
• Materials Science

Background:

• Photonic crystal fibers (PCFs) offer unique light-guiding properties.
• Interface roughness in PCFs can cause significant optical loss.
• Understanding scattering mechanisms is crucial for PCF performance.

Purpose of the Study:

• To theoretically analyze roughness scattering loss at hole interfaces in solid core PCFs.
• To compare theoretical predictions with experimental measurements.
• To investigate the impact of roughness spectrum on scattering loss.

Main Methods:

• Theoretical modeling of roughness scattering loss.
• Development of a roughness spectrum model based on capillary waves.
• Comparison of model predictions with experimental data from fabricated PCFs.

Main Results:

• The capillary wave roughness spectrum model shows good agreement with experimental loss in small core PCFs.
• Roughness scattering loss exhibits weak dependence on wavelength.
• Larger core sizes necessitate a long length-scale cut-off in the roughness spectrum for accurate modeling.

Conclusions:

• The capillary wave model provides a valid framework for understanding roughness scattering in PCFs.
• Scattering is non-Rayleigh due to long-range roughness correlations.
• The findings are essential for designing low-loss PCFs for various applications.