Simple effective medium approximation with Rayleigh scattering.

We present a simple analytical effective medium approximation (EMA) that can account for finite-sized and interacting inclusions in the Rayleigh scattering regime. The polarizability of an individual inclusion is calculated using the Mie solution and net polarizability is formed, leading to effective parameters. The Mie coefficients are expanded into polynomials and curtailed to the sixth order, which is accurate in the Rayleigh regime. Results obtained using the developed models are compared with experimental results and existing EMAs. The analytical formula outperforms other EMAs for large inclusion sizes, high filling factors, and high relative refractive indices.