Materials with near-zero refractive index have attracted much attention over the past decade due to the fascinating phenomena they enabled, such as energy squeezing in thin waveguides, engineering of wavefronts, and “photonic doping”. These materials are not directly available in nature, but can be realized in periodic artificial structures. Among near-zero refractive index materials, double-zero-index materials are a special type with both constitutive parameters vanishing simultaneously, leading to intriguing applications including arbitrarily shaped high-transmission waveguides, cloaking of inclusions, nonlinear enhancement, and directional emissions. This perspective focuses on the recent developments on double-zero-index materials, including their fundamental physics, design principles, experimental realizations, and potential applications.
Bibliographical noteFunding Information:
This work is supported by the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under Award No. OSR-CRG2020-4374 and the KAUST Baseline Research Fund under No. BAS/1/1626-01-01.
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ASJC Scopus subject areas
- Physics and Astronomy(all)