Intrinsically undamped plasmon modes in narrow electron bands
Name
20869.full.pdf
Description
Published version
Size
1.14 MB
Format
Adobe PDF
Checksum (MD5)
33eedf41c3e6f31b1dd5b3daabd747dc
Author(s)
Lewandowski, Cyprian Krzysztof
Levitov, Leonid
Date Issued
September 27, 2019
Journal
Proceedings of the National Academy of Sciences of the United States of America
Publisher
Proceedings of the National Academy of Sciences
Citation
Lewandowski, Cyprian and Leonid Levitov. "Intrinsically undamped plasmon modes in narrow electron bands." Proceedings of the National Academy of Sciences of the United States of America 116 (2019): 20869-20874 © 2019 The Author(s)
Version
Final published version
Abstract
Surface plasmons in 2-dimensional electron systems with narrow Bloch bands feature an interesting regime in which Landau damping (dissipation via electron–hole pair excitation) is completely quenched. This surprising behavior is made possible by strong coupling in narrow-band systems characterized by large values of the “fine structure” constant α = e2 /~κvF. Dissipation quenching occurs when dispersing plasmon modes rise above the particle–hole continuum, extending into the forbidden energy gap that is free from particle–hole excitations. The effect is predicted to be prominent in moiré graphene, where at magic twist-angle values, flat bands feature α 1. The extinction of Landau damping enhances spatial optical coherence. Speckle-like interference, arising in the presence of disorder scattering, can serve as a telltale signature of undamped plasmons directly accessible in near-field imaging experiments.
Subjects
Multidisciplinary
MIT Department
Massachusetts Institute of Technology. Department of Physics
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
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DOI of Published Version
https://doi.org/10.1073/pnas.1909069116
