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DOE OSTI · 1594103

Spin correlation in trigonal EuMn 2 As 2

Dahal, A.·Chen, Yiyao·Heitmann, T.·Thamizhavel, A.·Paramanik, U.·Dhar, S. K.·Singh, D. K.
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Abstract

The trigonal structure of EuMn 2 As 2 is an anomaly in the tetragonal 122-type pnictide family. Here, we report a detailed investigation of the underlying magnetic correlations in single crystal EuMn 2 As 2 using high-resolution elastic neutron-scattering measurements. The system undergoes two successive antiferromagnetic transitions at T = 135 K and 14.4 K, respectively. Numerical modeling of the experimental data reveals the long-range antiferromagnetic correlation of Mn-ions in the a - b plane below T N 1 = 135 K . Mn spins are aligned closer to the diagonal axis of the unit cell. The lower temperature transition, below T N 2 = 14.4 K , is discovered to arise due to the long-range antiferromagnetic correlation of Eu spins that are rotated by θ = 55 ° from the c axis of the unit cell.

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Dahal, A., Chen, Yiyao, Heitmann, T., Thamizhavel, A., Paramanik, U., Dhar, S. K., Singh, D. K.. 2019-02-25. Spin correlation in trigonal EuMn 2 As 2. https://doi.org/10.1103/physrevb.99.085135

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