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.… 展开作者
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
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 Néel temperature was closer determined for the first time from temperature dependence of magnetization, in agreement with our Monte Carlo simulations.
Room-temperature antiferromagnetic resonance in NaMnAs
Charles University（查理大学）；Laboratoire National des Champs Magnétiques Intenses, LNCMI-EMFL, CNRS UPR3228, Univ. Grenoble Alpes, Univ. Toulouse, Univ. Toulouse 3, INSA-T（强磁场国家实验室，LNCMI-EMFL，法国国家科学研究中心UPR3228，格勒诺布尔阿尔卑斯大学，图卢兹大学，图卢兹第三大学，国立应用科学学院图卢兹分校）；Institute of Physics, Academy of Science of the Czech Republic（捷克科学院物理研究所）；Department of Physics, University of Fribourg（弗里堡大学物理系）
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