On the limits of the effective description of hyperbolic materials in the presence of surface waves

Author(s): Maria Tschikin, Svend-Age Biehs, Riccardo Messina, Philippe Ben-Abdallah
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Article: J. Opt. 15 105101 (2013), Institute of Physics
Keywords: effective medium theory, hyperbolic multilayer structures, local density of states, surface waves, super-Planckian thermal radiation
Abstract:: Here, we address the question of the validity of an effective description for hyperbolic metamaterials in the near-field region. We show that the presence of localized modes such as surface waves drastically limits the validity of the effective description, and requires revisiting the concept of homogenization in the near-field. We demonstrate, from exact scattering matrix calculations for multilayer hyperbolic structures, that one can find surface modes in spectral regions where the effective approach predicts hyperbolic modes only. Hence, the presence of surface modes which are not accounted for in the effective description can lead to physical misinterpretations in the description of hyperbolic materials and their related properties. In particular, we discuss in detail how the choice of the topmost layer affects the validity of the effective medium approach for calculating the local density of states and the super-Planckian thermal radiation.
URL: doi:10.1088/2040-8978/15/10/105101; This shadow-file was created by My Meta Maker 1.6.1. Last Update: Wed Aug 28 11:55:01 2013