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Plasmonic response in metals, defined as the ability to support subwavelength confinement of surface plasmon modes, is typically limited to a narrow frequency range below the metals’ plasma frequency. This places severe limitations on the operational wavelengths of plasmonic materials and devices. However, when the volume of a metal film is massively decreased, highly confined quasi-two-dimensional surface plasmon modes can be supported out to wavelengths well beyond the plasma wavelength. While this has, thus far, been achieved using ultrathin (nm-scale) metals, such films are quite difficult to realize and suffer from even higher losses than bulk plasmonic films. To extend the plasmonic response to the infrared, here we introduce the concept of metaplasmonics, representing a novel plasmonic modality with a host of appealing properties. By fabricating and characterizing a series of metaplasmonic nanoribbons, we demonstrate large confinement, high-quality factors, and large near-field enhancements across a broad wavelength range, extending well beyond the limited bandwidth of traditional plasmonic materials. We demonstrate 35× plasmon wavelength reduction, and numerical simulations suggest that further wavelength reduction, up to a factor of 150, is achievable using our approach. The demonstration of the metaplasmonics paradigm offers a promising path to fill the near- and mid-infrared technological gap for high-quality plasmonic materials and provides a new material system to study the effects of extreme plasmonic confinement for applications in nonlinear and quantum plasmonics.
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Photoinduced electric effects in various plasmonic materials
Abstract Photoinduced voltages associated with surface plasmon polariton excitations are studied both theoretically and experimentally in various plasmonic systems as the function of material, wavelength, and type of structure. Experimental photovoltage normalized to the absorbed power shows a general decrease upon an increase in the wavelength, enhancement in the nanostructured samples, and a strong variation in the magnitude as a function of the material, which are not in line with the theoretical predictions of the simple plasmonic pressure approach. The results can be used for clarification of the mechanisms and further development of an adequate theoretical approach to the plasmon drag effect.
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- Award ID(s):
- 2112595
- PAR ID:
- 10422745
- Date Published:
- Journal Name:
- Journal of Physics: Condensed Matter
- Volume:
- 34
- Issue:
- 45
- ISSN:
- 0953-8984
- Page Range / eLocation ID:
- 455301
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1088/1361-648X/ac8cc7
