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arXiv · 1701.06293

Semiconductor-to-Metal Transition in the Bulk of WSe2 upon Potassium Intercalation

M. Ahmad·E. Müller·C. Habenicht·R. Schuster·M. Knupfer·B. Büchner
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Abstract

We present electron energy-loss spectroscopic measurements of potassium (K) intercalated tungsten diselenide (WSe2). After exposure of pristine WSe2 films to potassium, we observe a charge carrier plasmon excitation at about 0.97 eV, which indicates a semiconductor to metal transition. Our data signal the formation of one particular doped K-WSe2 phase. A Kramers-Kronig analysis (KKA) allows the determination of the dielectric function and to estimate the composition of about K0.6WSe2. Momentum dependent measurements reveal a substantial plasmon dispersion to higher energies.

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M. Ahmad, E. Müller, C. Habenicht, R. Schuster, M. Knupfer, B. Büchner. 2017-01-23. Semiconductor-to-Metal Transition in the Bulk of WSe2 upon Potassium Intercalation. https://doi.org/10.1088/1361-648x%2Faa63a7

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