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arXiv · 1209.2587

Plasmon Evolution and Charge-Density Wave Suppression in Potassium Intercalated Tantalum Diselenide

A. König·K. Koepernik·R. Schuster·R. Kraus·M. Knupfer·B. Büchner·H. Berger
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Abstract

We have investigated the influence of potassium intercalation on the formation of the charge-density wave (CDW) instability in 2H-tantalum diselenide by means of Electron Energy-Loss Spectroscopy and density functional theory. Our observations are consistent with a filling of the conduction band as indicated by a substantial decrease of the plasma frequency in experiment and theory. In addition, elastic scattering clearly points to a destruction of the CDW upon intercalation as can be seen by a vanishing of the corresponding superstructures. This is accompanied by a new superstructure, which can be attributed to the intercalated potassium. Based on the behavior of the c-axis upon intercalation we argue in favor of interlayer-sites for the alkali-metal and that the lattice remains in the 2H-modification.

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A. König, K. Koepernik, R. Schuster, R. Kraus, M. Knupfer, B. Büchner, H. Berger. 2012-10-09. Plasmon Evolution and Charge-Density Wave Suppression in Potassium Intercalated Tantalum Diselenide. https://doi.org/10.1209/0295-5075%2F100%2F27002

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