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

TITLE=Nuclear magnetic resonance studies in a model transverse field Ising system

JOURNAL=Frontiers in Physics

VOLUME=12

YEAR=2024

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2024.1393229

DOI=10.3389/fphy.2024.1393229

ISSN=2296-424X

ABSTRACT=<p>The suppression of ferroquadrupolar order in TmVO<sub>4</sub> 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.</p>