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arXiv · 1807.05404

Quantum continuum fluctuations in glassy perovskite Ca(Co$_{0.15}$Ru$_{0.85}$)O$_{3}$

Yiyao Chen·A. Dahal·J. Rodriguez-Rivera·G. Xu·T. Heitmann·V. Dugaev·A. Ernst·D. J. Singh·D. K. Singh
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Abstract

The quantum spin continuum and classical spin freezing, associated with a glassy state, represent two opposite extremes of a correlated electronic material. Here, we report the coexistence of a quantum spin continuum with a weak spin glass order in Co-doped CaRuO$_{3}$ perovskite near the chemical doping dependent metal-insulator transition boundary. Inelastic neutron measurements on Ca(Co$_{0.15}$Ru$_{0.85}$)O$_{3}$ at low temperature, $T$ = 1.5 K, reveal a continuum spectrum in the $Q-E$ space due to uncorrelated spin fluctuations. This persists across the glass transition at $T_G \simeq$23 K. Furthermore, scaling of the dynamic susceptibility yields a very small scaling coefficient $\alpha$ $\simeq$ 0.1, suggesting extreme locality of the dynamic properties. The experimental results indicate the realization of a narrow regime where the distinction between continuum dynamic behavior and glass-like regimes is reduced.

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Yiyao Chen, A. Dahal, J. Rodriguez-Rivera, G. Xu, T. Heitmann, V. Dugaev, A. Ernst, D. J. Singh, D. K. Singh. 2018-07-14. Quantum continuum fluctuations in glassy perovskite Ca(Co$_{0.15}$Ru$_{0.85}$)O$_{3}$. https://arxiv.org/abs/1807.05404

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