Electro-nuclear quantum phase transition in TmVO$_4$
Abstract
Hyperfine interactions couple nuclear and electronic degrees of freedom. The present work explores how hyperfine coupling within the Tm ions in TmVO single crystals affects an electronic ferroquadrupole ordered ground state and its associated field-tuned quantum phase transition. For temperatures below the hyperfine energy scale, the nuclear moments reduce the critical field for the electronic order, resulting in a dramatic back-bending of the phase boundary delineating the ferroquadrupole order. This behavior is well described by a single-ion semiclassical mean-field model. Moreover, analysis of the effective Hamiltonian leads to a prediction of spontaneous nuclear magnetic order mediated by 4 electrons, which in principle persists with the application of orthogonal antisymmetric strain, yielding a proposed electro-nuclear tetracritical point.
Cite
@article{arxiv.2509.11489,
title = {Electro-nuclear quantum phase transition in TmVO$_4$},
author = {Mark P. Zic and Chao Huan and Nicolas Silva and Yuntian Li and Mark W. Meisel and Ian R. Fisher},
journal= {arXiv preprint arXiv:2509.11489},
year = {2025}
}