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arXiv · 1202.1107

Spin Dynamics at Very Low Temperature in Spin Ice Dy$_2$Ti$_2$O$_7$

K. Matsuhira·C. Paulsen·E. Lhotel·C. Sekine·Z. Hiroi·S. Takagi
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Abstract

We have performed AC susceptibility and DC magnetic relaxation measurements on the spin ice system Dy$_2$Ti$_2$O$_7$ down to 0.08 K. The relaxation time of the magnetization has been estimated below 2 K down to 0.08 K. The spin dynamics of Dy$_2$Ti$_2$O$_7$ is well described by using two relaxation times ($τ_{\rm S}$ (short time) and $τ_{\rm L}$ (long time)). Both $τ_{\rm S}$ and $τ_{\rm L}$ increase on cooling. Assuming the Arrhenius law in the temperature range 0.5-1 K, we obtained an energy barrier of 9 K. Below 0.5 K, both $τ_{\rm S}$ and $τ_{\rm L}$ show a clear deviation from the thermal activated dynamics toward temperature independent relaxation, suggesting a quantum dynamics.

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K. Matsuhira, C. Paulsen, E. Lhotel, C. Sekine, Z. Hiroi, S. Takagi. 2012-02-06. Spin Dynamics at Very Low Temperature in Spin Ice Dy$_2$Ti$_2$O$_7$. https://doi.org/10.1143/jpsj.80.123711

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