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arXiv · 1411.4402

A Fundamental Limit on Propagation Loss of Waveguides with Subwavelength Mode Size

Amir Arbabi·Ehsan Arbabi·Safieddin Safavi-Naeini
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Abstract

A fundamental trade-off relation between the cross sectional confinement and propagation length of an arbitrary mode of a general waveguide is presented. This limit is a generalization of the well-known diffraction limit for guided modes. The results provide a lower bound on propagation loss of plasmonic waveguides which are attractive for their deep subwavelength mode dimensions. We also introduce a material loss merit factor that sets a criterion for comparing different plasmonic materials for achieving the best trade-off between confinement and loss.

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Amir Arbabi, Ehsan Arbabi, Safieddin Safavi-Naeini. 2014-11-17. A Fundamental Limit on Propagation Loss of Waveguides with Subwavelength Mode Size. https://arxiv.org/abs/1411.4402

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