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In two-dimensional electron systems, plasmons are gapless and long-lived collective excitations of propagating charge density oscillations. We study the fluctuation mechanism of plasmon-assisted transport in the regime of electron hydrodynamics. We consider pristine electron liquids where charge fluctuations are thermally induced by viscous stresses and intrinsic currents, while attenuation of plasmons is determined by the Maxwell mechanism of charge relaxation. It is shown that, while the contribution of plasmons to the shear viscosity and thermal conductivity of a Fermi liquid is small, plasmon resonances in the bilayer devices enhance the drag resistance. In systems without Galilean invariance, fluctuation-driven contributions to dissipative coefficients can be described only in terms of hydrodynamic quantities: intrinsic conductivity, viscosity, and plasmon dispersion relation.
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Infrared plasmons in ultrahigh conductive PdCoO2 metallic oxide
Abstract PdCoO 2 layered delafossite is the most conductive compound among metallic oxides, with a room-temperature resistivity of nearly $$2\,\mu \Omega \,{{{{{\rm{cm}}}}}}$$ 2 μ Ω cm , corresponding to a mean free path of about 600 Å. These values represent a record considering that the charge density of PdCoO 2 is three times lower than copper. Although its notable electronic transport properties, PdCoO 2 collective charge density modes (i.e. surface plasmons) have never been investigated, at least to our knowledge. In this paper, we study surface plasmons in high-quality PdCoO 2 thin films, patterned in the form of micro-ribbon arrays. By changing their width W and period 2 W , we select suitable values of the plasmon wavevector q , experimentally sampling the surface plasmon dispersion in the mid-infrared electromagnetic region. Near the ribbon edge, we observe a strong field enhancement due to the plasmon confinement, indicating PdCoO 2 as a promising infrared plasmonic material.
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- Award ID(s):
- 2004125
- PAR ID:
- 10440703
- Date Published:
- Journal Name:
- Communications Physics
- Volume:
- 5
- Issue:
- 1
- ISSN:
- 2399-3650
- 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/10.1038/s42005-022-00924-0
