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Hypergap Optical Materials

delete2025-10-02
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PRE
AI
X
Xiaolei Hu
X
Xiang Guo
Z
Zhengran Wu
K
Kun Chen
X
Xintian Chen
Z
Zhilin Li
L
Ling Lü *
DOI:10.1002/adma.202512769delete
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Abstract

Abstract

En 中文
Optical materials primarily refer to transparent insulators and semiconductors for guiding, diffracting, and nonlinearly-generating light at photon energies below the electronic bandgaps. This work proposes that a solid can be equally lossless, above the fundamental bandgap, in an energy interval dubbed the hypergap, when the conduction and valence bands are well-isolated. The optics within the hypergap could defy the conventional rules and limits set by the bandgap materials, including the low-loss negative permittivity unavailable in existing metals, the anomalous-dispersion phase matching in crystals without birefringence or microstructures, as well as the negative group-velocity dispersion across the visible spectrum unattainable in known dielectrics. High-throughput searches are performed in comprehensive material databases, predict over a hundred hypergap candidates, and experimentally verify one of them. Therefore, hypergap materials might lead to lower loss plasmonic metamaterials, easier wavelength converters in nonlinear optics, and simpler pulse stretchers or compressors in ultrafast optics, potentially transforming optics with unexplored material opportunities.
Keywords:
DFT calculations
high-throughput search
optical materials

Journal

Advanced Materials cover
Advanced Materials
IF:
26.8
Papers:
3.4W
Citations:
46.0W

Organization

No organization information available