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arXiv · 2109.03348

Single crystal studies and electronic structure investigation of a room-temperature semiconductor NaMnAs

J. Volny·V. Holy·K. Charvatova·M. Veis·M. Vondracek·J. Honolka·E. Duverger-Nedellec·J. Schusser·S. W. D'Souza·J. Minar·J. M. Pientka·A. Marmodoro·K. Vyborny·K. Uhlirova
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Abstract

We report synthesis of single crystalline NaMnAs, confirm its antiferromagnetic order and characterise the sample by photoemission spectroscopy. The electronic structure was studied using optical transmittance, x-ray and ultraviolet spectroscopy and by theoretical modeling using local density approximation (LDA) extended to LDA+U when Heisenberg model parameters were determined. Optical transmittance measurement have confirmed the theoretical predictions that NaMnAs is a semiconductor. Also the N\'eel temperature was closer determined for the first time from temperature dependence of magnetization, in agreement with our Monte Carlo simulations.

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J. Volny, V. Holy, K. Charvatova, M. Veis, M. Vondracek, J. Honolka, E. Duverger-Nedellec, J. Schusser, S. W. D'Souza, J. Minar, J. M. Pientka, A. Marmodoro, K. Vyborny, K. Uhlirova. 2021-09-07. Single crystal studies and electronic structure investigation of a room-temperature semiconductor NaMnAs. https://doi.org/10.1103/physrevb.105.125204

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