Detailed comparison of recent-and dissimilar-effective-medium models incorporating dependent scattering

Area of Science:

• Physics
• Optics
• Materials Science

Background:

• Effective-medium models predict the optical properties of composite materials.
• Two new models based on the quasi-crystalline approximation exist for turbid suspensions.
• These models differ significantly in their approximations beyond the quasi-crystalline approximation.

Purpose of the Study:

• To compare predictions of two distinct effective-medium models for turbid particle suspensions.
• To determine the applicability range of these models concerning particle parameters and volume fractions.
• To investigate the conditions under which these dissimilar models yield similar results.

Main Methods:

• Comparison of predictions from two recently derived effective-medium models.
• Analysis of the effective refractive index for varying particle sizes, volume fractions, and refractive index contrasts.
• Evaluation of model applicability in the regime of dependent scattering.

Main Results:

• Both models surprisingly yield very similar predictions for the effective refractive index.
• This agreement holds for volume fractions up to 0.4.
• Similar results are observed for particles comparable to or larger than the wavelength and for a wide range of refractive index contrasts.

Conclusions:

• The two models show remarkable agreement in their predictions for effective refractive index under various conditions.
• These findings enhance confidence in the validity and applicability of both effective-medium models.
• The study clarifies the range of validity for these models in dense suspensions where dependent scattering is significant.