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arXiv · 2402.18519

Nuclear magnetic resonance studies in a model transverse field Ising system

Y-H. Nian·I. Vinograd·C. Chaffey·Y. Li·M. P. Zic·P. Massat·R. R. P. Singh·I. R. Fisher·N. J. Curro
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Abstract

The suppression of ferroquadrupolar order in TmVO$_4$ in a magnetic field is well-described by the transverse field Ising model, enabling detailed studies of critical dynamics near the quantum phase transition. We describe nuclear magnetic resonance measurements in pure and Y-doped single crystals. The non-Kramers nature of the ground state doublet leads to a unique form of the hyperfine coupling that exclusively probes the transverse field susceptibility. Our results show that this quantity diverges at the critical field, in contrast to the mean-field prediction. Furthermore, we find evidence for quantum critical fluctuations present near Tm-rich regions in Y-doped crystals at levels beyond which long-range order is suppressed, suggesting the presence of quantum Griffiths phases.

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Y-H. Nian, I. Vinograd, C. Chaffey, Y. Li, M. P. Zic, P. Massat, R. R. P. Singh, I. R. Fisher, N. J. Curro. 2024-02-28. Nuclear magnetic resonance studies in a model transverse field Ising system. https://doi.org/10.3389/fphy.2024.1393229

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