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arXiv · 1212.1808

Faraday Rotation and Circular Dichroism Spectra of Gold and Silver Nanoparticle Aggregates

Sahar Pakdel·MirFaez Miri
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Abstract

We study the magneto-optical response of noble metal nanoparticle clusters. We consider the interaction between the light-induced dipoles of particles. In the presence of a magnetic field, the simplest achiral cluster, a dimer, exhibits circular dichroism (CD). The CD of a dimer depends on the directions of the magnetic field and the light wave vector. The CD of a populous cluster weakly depends on the magnetic field. Upon scattering from the cluster, an incident linearly polarized light with polarization azimuth $φ$, becomes elliptically polarized. The polarization azimuth rotation and ellipticity angle variation are sinusoidal functions of $2 φ$. The anisotropy and the chirality of the cluster control the amplitude and offset of these sinusoidal functions. The Faraday rotation and Faraday ellipticity are also sinusoidal functions of $2 φ$. Near the surface plasmon frequency, Faraday rotation and Faraday ellipticity increase.

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Sahar Pakdel, MirFaez Miri. 2012-12-08. Faraday Rotation and Circular Dichroism Spectra of Gold and Silver Nanoparticle Aggregates. https://doi.org/10.1103/physrevb.86.235445

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