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Dynamic Lattice Distortions in Sr$_2$RuO$_4$: A microscopic study by perturbed angular correlation (TDPAC) spectroscopy

S. N. Mishra·M. Rots·S. Cottenier
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Abstract

Applying time differential perturbed angular correlation (TDPAC) spectroscopy and \emph{ab initio} calculations, we have investigated possible lattice instabilities in Sr$_{2}$RuO$_{4}$ by studying the electric quadrupole interaction of a $^{111}$Cd probe at the Ru site. We find evidence for a dynamic lattice distortion, revealed from the observations of: (i) a rapidly fluctuating electric-field gradient (EFG) tensor of which the main component decreases with decreasing temperature, and (ii) a monotonic increase of the EFG asymmetry ($η$) below 300 K. We argue that the observed dynamic lattice distortion is caused by strong spin fluctuations associated with the inherent magnetic instability of Sr$_{2}$RuO$_{4}$.

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S. N. Mishra, M. Rots, S. Cottenier. 2007-01-04. Dynamic Lattice Distortions in Sr$_2$RuO$_4$: A microscopic study by perturbed angular correlation (TDPAC) spectroscopy. https://arxiv.org/abs/cond-mat/0701068

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