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arXiv · 2307.05223

Plasmonic polarons induced by alkali-atom deposition in hafnium disulfide (1$T$-HfS$_2$)

Christoph Emeis·Sanjoy Kr Mahatha·Sebastian Rohlf·Kai Rossnagel·Fabio Caruso
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Abstract

We combine ab-initio calculations based on many-body perturbation theory and the cumulant expansion with angle-resolved photoemission spectroscopy (ARPES) to quantify the electron-plasmon interaction in the highly-doped semiconducting transition metal dichalcogenide 1$T$-HfS$_2$. ARPES reveals the emergence of satellite spectral features in the vicinity of quasiparticle excitations at the bottom of the conduction band, suggesting coupling to bosonic excitations with a characteristic energy of 200 meV. Our first-principles calculations of the photoemission spectral function reveal that these features can be ascribed to electronic coupling to carrier plasmons (doping-induced collective charge-density fluctuations). We further show that reduced screening at the surface enhances the electron-plasmon interaction and is primarily responsible for the emergence of plasmonic polarons.

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Christoph Emeis, Sanjoy Kr Mahatha, Sebastian Rohlf, Kai Rossnagel, Fabio Caruso. 2023-07-11. Plasmonic polarons induced by alkali-atom deposition in hafnium disulfide (1$T$-HfS$_2$). https://arxiv.org/abs/2307.05223

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