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Title: Nuclear magnetic resonance studies in a model transverse field Ising system
The suppression of ferroquadrupolar order in TmVO4in 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.  more » « less
Award ID(s):
2210613
PAR ID:
10517183
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Frontiers Media S.A.
Date Published:
Journal Name:
Frontiers in Physics
Volume:
12
ISSN:
2296-424X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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