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arXiv · 1205.4929

Optical angular momentum in dispersive media

T. G. Philbin·O. Allanson
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Abstract

The angular momentum density and flux of light in a dispersive, rotationally symmetric medium are derived from Noether's theorem. Optical angular momentum in a dispersive medium has no simple relation to optical linear momentum, even if the medium is homogeneous. A circularly polarized monochromatic beam in a homogeneous, dispersive medium carries a spin angular momentum of $\pm\hbar$ per energy $\hbar\omega$, as in vacuum. This result demonstrates the non-trivial interplay of dispersive contributions to optical angular momentum and energy.

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T. G. Philbin, O. Allanson. 2012-05-22. Optical angular momentum in dispersive media. https://doi.org/10.1103/physreva.86.055802

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