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arXiv · 1207.2360

Optical properties of the iron-pnictide analog BaMn2As2

A. Antal·T. Knoblauch·Y. Singh·P. Gegenwart·D. Wu·M. Dressel
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Abstract

We have investigated the infrared and Raman optical properties of BaMn2As2 in the ab-plane and along the c-axis. The most prominent features in the infrared spectra are the Eu and A2u phonon modes which show clear TO-LO splitting from the energy loss function analysis. All the phonon features we observed in infrared and Raman spectra are consistent with the calculated values. Compared to the iron-pnictide analog AFe2As2, this compound is much more two-dimensional in its electronic properties. For E || c-axis, the overall infrared reflectivity is insulating like. Within the ab-plane the material exhibits a semiconducting behavior. An energy gap 2Δ=48 meV can be clearly identified below room temperature.

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A. Antal, T. Knoblauch, Y. Singh, P. Gegenwart, D. Wu, M. Dressel. 2012-07-10. Optical properties of the iron-pnictide analog BaMn2As2. https://doi.org/10.1103/physrevb.86.014506

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