This tool does uses FDTD method to quantitatively determine the reflection and transmission co-efficient of a metallic (silver and gold) and dielectric nano-particle.
Aleksandar D. Rakic, Aleksandra B. Djurišic, Jovan M. Elazar, and Marian L. Majewski, "Optical Properties of Metallic Films for Vertical-Cavity Optoelectronic Devices," Appl. Opt. 37, 5271-5283 (1998)
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