Induced Random Fields in the LiHo${}_x$Y${}_{1-x}$F${}_4$ Quantum Ising Magnet in a Transverse Magnetic Field

Abstract

The LiHo${}_x$Y${}_{1-x}$F${}_4$ magnetic material in a transverse magnetic field $B_x\hat{x}$ perpendicular to the Ising spin direction has long been used to study tunable quantum phase transitions in a random disordered system. We show that the $B_x-$induced magnetization along the $\hat{x}$ direction, combined with the local random dilution-induced destruction of crystalline symmetries, generates, via the predominant dipolar interactions between Ho${}^{3+}$ ions, {\it random fields} along the Ising $\hat{z}$ direction. This identifies LiHo${}_x$Y${}_{1-x}$F${}_4$ in $B_x$ as a new random field Ising system. The random fields explain the rapid decrease of the critical temperature in the diluted ferromagnetic regime and the smearing of the nonlinear susceptibility at the spin glass transition with increasing $B_x$, and render the $B_x-$induced quantum criticality in LiHo${}_x$Y${}_{1-x}$F${}_4$ likely inaccessible.

Version #2. Three figures. Slight modification of abstract compared to version #1. Minor typos corrected. To appear in Physical Review Letters

References in corpus (1)

• Absence of an Almeida-Thouless line in Three-Dimensional Spin Glasses

Cited by in corpus (12)

• Quantum and Classical Glass Transitions in $LiH{o}_x{Y}_{1-x}{F}_4$
• Ferromagnet in a continuously tuneable random field
• $\mathrm{LiH}{\mathrm{o}}_{\mathrm{x}}{\mathrm{Y}}_{1-\mathrm{x}}{\mathrm{F}}_4$ as a random field Ising ferromagnet
• The low-$T$ phase diagram of $\mathrm{LiH}{\mathrm{o}}_{\mathrm{x}}{\mathrm{Y}}_{1-\mathrm{x}}{\mathrm{F}}_4$
• Absence of Conventional Spin-Glass Transition in the Ising Dipolar System LiHo_xY_{1-x}F_4
• Phase diagram of the dilute magnet LiHo_xY_{1-x}F_4
• Low-temperature properties of the dilute dipolar magnet LiHo_xY_(1-x)F_4
• Perturbative Quantum Monte Carlo Study of LiHoF4 in a Transverse Magnetic Field
• Effective Spin-1/2 Description of Transverse-Field-Induced Random Fields in Dipolar Spin Glasses with Strong Single-Ion Anisotropy
• Thermal expansion and Grueneisen parameter in quantum Griffiths phases
• Quantum spin glass in anisotropic dipolar systems
• Assessment of the RE(OH)3 Ising-like Magnetic Materials as Possible Candidates for the Study of Transverse-Field-Induced Quantum Phase Transitions