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arXiv · 1707.00997

Spin wave dispersion just above the magnetic order-order transition in the metallic antiferromagnet Mn$_3$Pt

Soshi Ibuka·Tetsuya Yokoo·Shinichi Itoh·Kazuya Kamazawa·Mitsutaka Nakamura·Motoharu Imai
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Abstract

Spin wave dispersion in the metallic antiferromagnet Mn$_3$Pt was investigated just above the order-order transition temperature by using the inelastic neutron scattering technique. The spin wave dispersion at $T = 400$ K along [100], [110] and [111] directions was isotropic within the measurement accuracy. The dispersion was described by $({\hbarω})^2 = c^2q^2 + Δ^2$ with $c = 190$ meV Å and $Δ= 3.3$ meV. Compared with the dispersion at $T = 419$ K previously reported, the result demonstrates a large reduction of the stiffness constant $c$ with increasing temperature. This is similar to that observed in the metallic antiferromagnet FePt$_3$, and is an indication of the itinerancy of the magnetic moments.

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Soshi Ibuka, Tetsuya Yokoo, Shinichi Itoh, Kazuya Kamazawa, Mitsutaka Nakamura, Motoharu Imai. 2017-07-05. Spin wave dispersion just above the magnetic order-order transition in the metallic antiferromagnet Mn$_3$Pt. https://doi.org/10.1088/1742-6596%2F868%2F1%2F012017

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