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arXiv · 1507.00752

Exact dipolar moments of a localized electric current distribution

Ivan Fernandez-Corbaton·Stefan Nanz·Rasoul Alaee·Carsten Rockstuhl
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Abstract

The multipolar decomposition of current distributions is used in many branches of physics. Here, we obtain new exact expressions for the dipolar moments of a localized electric current distribution. The typical integrals for the dipole moments of electromagnetically small sources are recovered as the lowest order terms of the new expressions in a series expansion with respect to the size of the source. All the higher order terms can be easily obtained. We also provide exact and approximated expressions for dipoles that radiate a definite polarization handedness (helicity). Formally, the new exact expressions are only marginally more complex than their lowest order approximations.

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Ivan Fernandez-Corbaton, Stefan Nanz, Rasoul Alaee, Carsten Rockstuhl. 2015-07-01. Exact dipolar moments of a localized electric current distribution. https://doi.org/10.1364/oe.23.033044

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