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DOE OSTI · 2863346

Temperature-dependent spin dynamics in Cr 2 O 3

Sun, Qiyang·Wei, Bin·Su, Yaokun·Abernathy, Douglas L.·Li, Chen
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Abstract

Cr 2 ⁢O 3 emerges as a prominent candidate material for spintronics and magnetoelectronic applications. However, a comprehensive understanding of its temperature-dependent spin dynamics remains elusive, impeding the engineering of novel spintronics based on this material. Here, we delve into this through a combination of inelastic neutron scattering experiments and atomistic simulations. Our results unveiled the emergence of paramagnons above and below 𝑇 𝑁 . We demonstrated a significant softening of linear magnons upon heating in the antiferromagnetic state. Further analysis revealed that this softening primarily originated from four-magnon interactions, while thermal expansion played a minor role.

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Sun, Qiyang, Wei, Bin, Su, Yaokun, Abernathy, Douglas L., Li, Chen. 2024-08-12. Temperature-dependent spin dynamics in Cr 2 O 3. https://doi.org/10.1103/physrevb.110.064413

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