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arXiv · 1810.10487

Free-carrier dynamics in Au$_{2}$Pb probed by optical conductivity measurements

R. Kemmler·R. Hübner·A. Löhle·D. Neubauer·I. Voloshenko·L. M. Schoop·M. Dressel·A V. Pronin
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Abstract

We measured the optical reflectivity of the Dirac material Au$_{2}$Pb in a broad frequency range (30 - 48 000 cm$^{-1}$) for temperatures between 9 and 300 K. The optical conductivity, computed from the reflectivity, is dominated by free-carrier contributions from topologically trivial bulk bands at all temperatures. The temperature-independent total plasma frequency of these carriers is 3.9 $\pm$ 0.2 eV. Overall, optical response of Au$_{2}$Pb is typically metallic with no signs of localization and bad-metal behavior.

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R. Kemmler, R. Hübner, A. Löhle, D. Neubauer, I. Voloshenko, L. M. Schoop, M. Dressel, A V. Pronin. 2018-10-24. Free-carrier dynamics in Au$_{2}$Pb probed by optical conductivity measurements. https://doi.org/10.1088/1361-648x/aae7b1

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