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DOE OSTI · 2863346

Temperature-dependent spin dynamics in Cr 2 O 3

Sun, Qiyang [Univ. of California, Riverside, CA (United States)]·Wei, Bin [Henan Polytechnic Univ. (China)] (ORCID:0000000301251760)·Su, Yaokun [Univ. of California, Riverside, CA (United States)] (ORCID:0000000246207432)·Abernathy, Douglas L. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:000000023533003X)·Li, Chen [Univ. of California, Riverside, CA (United States)] (ORCID:0000000207585334)
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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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antiferromagnetismparamagnetismspin dynamicsspin waves

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Sun, Qiyang [Univ. of California, Riverside, CA (United States)], Wei, Bin [Henan Polytechnic Univ. (China)] (ORCID:0000000301251760), Su, Yaokun [Univ. of California, Riverside, CA (United States)] (ORCID:0000000246207432), Abernathy, Douglas L. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:000000023533003X), Li, Chen [Univ. of California, Riverside, CA (United States)] (ORCID:0000000207585334). 2024-08-12. Temperature-dependent spin dynamics in Cr 2 O 3. https://doi.org/10.1103/physrevb.110.064413

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