A novel hybrid plasmonic‐germanium telluride (GeTe) metasurface design, which demonstrates single‐peak on/off tunability across a spectral range of 2.5–7.5 μm is developed. Unlike previous metasurface designs utilizing GeTe layers as spacers, this study integrates GeTe as part of the meta‐atoms with gold (Au), significantly reducing the amount of GeTe required while achieving substantial on/off contrast. By varying the sizes of the meta‐atoms, different resonant wavelengths are achieved. This work represents a significant advancement in chalcogenide‐based active metasurfaces, providing precise and dynamic control over thermal emission properties.
This content will become publicly available on May 23, 2025
Enhancing metasurface fabricability through minimum feature size enforcement
The metasurfaces have shown great potential for miniaturizing conventional optics while offering extended flexibility. Recently, there has been considerable interest in using algorithms to generate meta-atom shapes for these metasurfaces, as they offer vast design freedom and not biased by the human intuition. However, these complex designs significantly increase the difficulty of fabrication. To address this, we introduce a design process that rigorously enforces the fabricability of both the material-filled (fill) and empty (void) regions in a metasurface design. This process takes into account specific constraints regarding the minimum feature size for each region. Additionally, it corrects any violations of these constraints across the entire device, ensuring only minimal impact on performance. Our method provides a practical way to create metasurface designs that are easy to fabricate, even with complex shapes, hence improving the overall production yield of these advanced meta-optical components.
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- Award ID(s):
- 2305139
- PAR ID:
- 10549309
- Publisher / Repository:
- De Gruyter
- Date Published:
- Journal Name:
- Nanophotonics
- Volume:
- 13
- Issue:
- 17
- ISSN:
- 2192-8614
- Page Range / eLocation ID:
- 3147 to 3154
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Phase, polarization, amplitude, and frequency represent the basic dimensions of light, playing crucial roles for both fundamental light–material interactions and all major optical applications. Metasurfaces have emerged as a compact platform to manipulate these knobs, but previous metasurfaces have limited flexibility to simultaneous control them. A multi‐freedom metasurface that can simultaneously and independently modulate phase, polarization, and amplitude in an analytical form is introduced, and frequency multiplexing is further realized by a
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