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arXiv · 1306.3413

Low-Dilution Limit of Zn_{1-x}Mn_{x}GeAs_{2}: electrical and magnetic properties

L. Kilanski·K. Szałowski·R. Szymczak·M. Górska·E. Dynowska·P. Aleshkevych·A. Podgórni·A. Avdonin·W. Dobrowolski·I. V. Fedorchenko·S. F. Marenkin
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Abstract

We present the studies of electrical transport and magnetic interactions in Zn_{1-x}Mn_{x}GeAs_{2} crystals with low Mn content 0 \leq x \leq 0.043. We show that the ionic-acceptor defects are mainly responsible for the strong p-type conductivity of our samples. We found that the negative magnetoresistance (MR) with maximum values of about -50% is related to the weak localization phenomena. The magnetic properties of Zn1-xMnxGeAs2 samples show that the random Mn-distribution in the cation sites of the host lattice occurs only for the sample with the lowest Mn-content, x=0.003. The samples with higher Mn-content show a high level of magnetic frustration. Nonzero Curie-Weiss temperature observed in all our samples indicates that weak ferromagnetic (for x=0.003) or antiferromagnetic (for x>0.005) interactions with |{\Theta}|<3 K are present in this system. The RKKY model, used to estimate the Mn-hole exchange integral Jpd for the diluted Zn/0.997/Mn/0.003/GeAs/2/ sample, makes possible to estimate the value of Jpd =(0.75+/-0.09) eV.

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L. Kilanski, K. Szałowski, R. Szymczak, M. Górska, E. Dynowska, P. Aleshkevych, A. Podgórni, A. Avdonin, W. Dobrowolski, I. V. Fedorchenko, S. F. Marenkin. 2013-06-14. Low-Dilution Limit of Zn_{1-x}Mn_{x}GeAs_{2}: electrical and magnetic properties. https://doi.org/10.1063/1.4820475

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