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Updated: Jun 25, 2025
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Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating
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Plasmon Excitations across the Charge-Density-Wave Transition in Single-Layer TiSe2
Zahra Torbatian1, Dino Novko2,3
1School of Nano Science, Institute for Research in Fundamental Sciences (IPM), 19395-5531 Tehran, Iran.
The Journal of Physical Chemistry Letters
|May 31, 2024
Summary
Single-layer 1T-TiSe2 exhibits a unique 2D plasmon mode. This mode
Area of Science:
- Condensed Matter Physics
- Materials Science
- Solid State Physics
Background:
- 1T-TiSe2 is theorized to have a soft electronic mode responsible for exciton condensation and charge-density-wave (CDW) transitions.
- Understanding collective electronic excitations is crucial for elucidating these phenomena.
Purpose of the Study:
- To investigate collective electronic excitations in single-layer 1T-TiSe2.
- To explore the scattering pathways of the 2D plasmon mode near the CDW phase.
Main Methods:
- Utilized *ab initio* electromagnetic linear response calculations.
- Analyzed the behavior of the 2D plasmon mode across the CDW transition temperature (T_CDW).
Main Results:
- Identified plasmon-phonon scattering as a dominant interaction.
- Observed strong hybridization between 2D plasmon and CDW excitations below T_CDW.
- Found anomalous temperature dependence in plasmon line width due to scattering and CDW gap excitations.
Conclusions:
- The interplay of plasmon-phonon scattering and CDW gap excitations dictates the plasmon's anomalous temperature dependence.
- Tunable optical features arise from temperature-dependent electronic structure modifications and electron-phonon coupling.
- CDW-bearing systems show potential for optoelectronics and low-loss plasmonics.
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