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arXiv · 2609.34870

A three-phase framework for photon scattering in porous nanocomposites

Khalid Alhammadi·Daniel Carne·Xiulin Ruan
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Abstract

Light scattering in heterogeneous media underpins a broad range of natural phenomena and optical technologies, yet remains difficult to understand in porous nanocomposites. State-of-the-art theories generally treat these materials as two-phase systems consisting of particles and a matrix, overlooking the air pores that are intrinsically present in porous composites. Here we experimentally determine the scattering coefficients of six BaSO4-acrylic and TiO2-acrylic coatings spanning a range of particle volume fractions and develop a three-phase scattering framework that explicitly accounts for pore-induced scattering. By representing the composite as two coupled scattering subsystems, particle-matrix and particle-air, the framework resolves discrepancies between theory and experiment: conventional two phase models substantially underpredict scattering in BaSO4 coatings while overpredicting scattering in TiO2 coatings, whereas the three-phase model accurately captures the observed trends and reduces the mean absolute logarithmic error from 0.667 to 0.379. This framework identifies air pores as a fundamental and independently controllable contributor to optical scattering, providing new physical insights and design principles for engineering highly scattering porous nanocomposites.

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Khalid Alhammadi, Daniel Carne, Xiulin Ruan. 2026-09-28. A three-phase framework for photon scattering in porous nanocomposites. https://arxiv.org/abs/2609.34870

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