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arXiv · 1007.0442

Spin glassiness and power law scaling in a quasi-triangular spin-1/2 compound

Jian Wu·Julia S. Wildeboer·Fletcher Werner·Alexander Seidel·Z. Nussinov·S. A. Solin
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Abstract

We present data on the magnetic properties of two classes of layered spin S=1/2 antiferromagnetic quasi-triangular lattice materials: $Cu_{2(1-x)}Zn_{2x}(OH)_3NO_3$ ($0 < x < 0.65$) and its long chain organic derivatives $Cu_{2(1-x)}Zn_{2x}(OH)_3(C_7H_{15}COO)\cdot mH_2O$ ($0 < x < 0.29$), where non-magnetic Zn substitutes Cu isostructurally. It is found that the long-chain compounds, even in a clean system in the absence of dilution, $x\!=\!0$, show spin-glass behavior, as evidenced by DC and AC susceptibility, and by time dependent magnetization measurements. A striking feature is the observation of a sharp crossover between two successive power law regimes in the DC susceptibility above the freezing temperature. Specific heat data are consistent with a conventional phase transition in the unintercalated compounds, and glassy behavior in the long chain compunds.

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Jian Wu, Julia S. Wildeboer, Fletcher Werner, Alexander Seidel, Z. Nussinov, S. A. Solin. 2010-07-02. Spin glassiness and power law scaling in a quasi-triangular spin-1/2 compound. https://doi.org/10.1209/0295-5075%2F93%2F67001

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