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Muon Spin Relaxation and Susceptibility Studies of Pure and Doped Spin 1/2 Kagomé-like system (Cu$_x$Zn$_{1-x}$)$_{3}$V$_{2}$O$_7$(OH)$_{2}$ 2H$_2$O

A. Fukaya·Y. Fudamoto·I. M. Gat·T. Ito·M. I. Larkin·A. T. Savici·Y. J. Uemura·P. P. Kyriakou·G. M. Luke·M. T. Rovers·K. M. Kojima·A. Keren·M. Hanawa·Z. Hiroi
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Abstract

Muon spin relaxation ($μ$SR) and magnetic susceptibility measurements have been performed on the pure and diluted spin 1/2 kagomé system (Cu$_x$Zn$_{1-x}$)$_{3}$V$_{2}$O$_7$(OH)$_{2}$ 2H$_2$O. In the pure $x=1$ system we found a slowing down of Cu spin fluctuations with decreasing temperature towards $T \sim 1$ K, followed by slow and nearly temperature-independent spin fluctuations persisting down to $T$ = 50 mK, indicative of quantum fluctuations. No indication of static spin freezing was detected in either of the pure ($x$=1.0) or diluted samples. The observed magnitude of fluctuating fields indicates that the slow spin fluctuations represent an intrinsic property of kagomé network rather than impurity spins.

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A. Fukaya, Y. Fudamoto, I. M. Gat, T. Ito, M. I. Larkin, A. T. Savici, Y. J. Uemura, P. P. Kyriakou, G. M. Luke, M. T. Rovers, K. M. Kojima, A. Keren, M. Hanawa, Z. Hiroi. 2003-10-30. Muon Spin Relaxation and Susceptibility Studies of Pure and Doped Spin 1/2 Kagomé-like system (Cu$_x$Zn$_{1-x}$)$_{3}$V$_{2}$O$_7$(OH)$_{2}$ 2H$_2$O. https://doi.org/10.1103/physrevlett.91.207603

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