期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:2018
卷号:115
期号:12
页码:2878-2883
DOI:10.1073/pnas.1718264115
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:The control and manipulation of thermal fields is a key scientific and technological challenge, usually addressed with nanophotonic structures with a carefully designed geometry. Here, we theoretically investigate a different strategy based on epsilon-near-zero (ENZ) media. We demonstrate that thermal emission from ENZ bodies is characterized by the excitation of spatially static fluctuating fields, which can be resonantly enhanced with the addition of dielectric particles. The “spatially static” character of these temporally dynamic fields leads to enhanced spatial coherence on the surface of the body, resulting in directive thermal emission. By contrast with other approaches, this property is intrinsic to ENZ media and it is not tied to its geometry. This point is illustrated with effects such as geometry-invariant resonant emission, beamforming by boundary deformation, and independence with respect to the position of internal particles. We numerically investigate a practical implementation based on a silicon carbide body containing a germanium rod.