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arXiv · 2007.04761

Dynamic Spin Fluctuations in the Frustrated A-site Spinel CuAl2O4

Hwanbeom Cho·R. Nirmala·Jaehong Jeong·Peter J. Baker·Hikaru Takeda·Nobuyoshi Mera·Stephen J. Blundell·Masashi Takigawa·D. T. Adroja·Je-Geun Park
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Abstract

We performed nuclear magnetic resonance (NMR) and muon spin relaxation ({\mu}SR) experiments to identify the magnetic ground state of the frustrated quantum A-site spinel, CuAl2O4. Our results verify that the ground state does not exhibit a long-range magnetic ordering, but a glass-like transition manifests at T*=2.3 K. However, the Gaussian shape and the weak longitudinal field dependence of {\mu}SR spectra below T* show that the ground state has dynamic spin fluctuations, distinct from those of conventional spin-glasses.

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Hwanbeom Cho, R. Nirmala, Jaehong Jeong, Peter J. Baker, Hikaru Takeda, Nobuyoshi Mera, Stephen J. Blundell, Masashi Takigawa, D. T. Adroja, Je-Geun Park. 2020-07-09. Dynamic Spin Fluctuations in the Frustrated A-site Spinel CuAl2O4. https://doi.org/10.1103/physrevb.102.014439

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