Experimental Phase Diagram and Dynamics of a Dilute Dipolar-Coupled Ising System

Abstract

We present ac susceptibility and specific heat measurements taken on samples of LiHo${}_x$Y${}_{1-x}$F${}_4$ in the dilute limit: x = 0.018, 0.045, 0.080 and 0.12. Susceptibility measurements show glassy behavior including wide absorption spectra that continually broaden with decreasing temperature. Dynamical scaling analyses show evidence of finite-temperature spin-glass transitions, the temperatures of which match those of recent theoretical work. A surprisingly long intrinsic time constant is observed in these samples and is found to be inversely correlated with the concentration of magnetic moments, x. Our results support the picture that this behavior is largely a single-ion effect, related to the random transverse fields generated by the off-diagonal component of the dipolar interaction and significantly slowed by the important nuclear hyperfine interaction. Specific heat measurements show broad features due to the electronic spins on top of a large Schottky-like nuclear contribution. Unusually, the peak position of the electronic component is found to be largely concentration independent, unlike the glass transition temperature.

References in corpus (17)

• Dynamically-Induced Frustration as a Route to a Quantum Spin Ice State in Tb2Ti2O7 via Virtual Crystal Field Excitations and Quantum Many-Body Effects
• Universality in three-dimensional Ising spin glasses: A Monte Carlo study
• Low Temperature Spin Freezing in Dy2Ti2O7 Spin Ice
• Induced Random Fields in the LiHo${}_x$Y${}_{1-x}$F${}_4$ Quantum Ising Magnet in a Transverse Magnetic Field
• Ferromagnet in a continuously tuneable random field
• Quantum and Classical Glass Transitions in $LiH{o}_x{Y}_{1-x}{F}_4$
• $\mathrm{LiH}{\mathrm{o}}_{\mathrm{x}}{\mathrm{Y}}_{1-\mathrm{x}}{\mathrm{F}}_4$ 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
• Spin Glass Transition at Nonzero Temperature in a Disordered Dipolar Ising System: The Case of LiHoxY{1-x}F4
• Phase diagram of the dilute magnet LiHo_xY_{1-x}F_4
• Specific Heat of the Dilute Ising Magnet LiHo${}_x$Y${}_{1-x}$F${}_4$
• Perturbative Quantum Monte Carlo Study of LiHoF4 in a Transverse Magnetic Field
• Low-temperature properties of the dilute dipolar magnet LiHo_xY_(1-x)F_4
• Existence of a phase transition under finite magnetic field in the long-range RKKY Ising spin glass Dy${}_x$Y${}_{1-x}$Ru${}_2$Si${}_2$
• Quantum Projection in an Ising Spin Liquid
• Effective Spin-1/2 Description of Transverse-Field-Induced Random Fields in Dipolar Spin Glasses with Strong Single-Ion Anisotropy

Cited by in corpus (12)

• Far from equilibrium quantum magnetism with ultracold polar molecules
• Dimensionality and irreversibility of field-induced transitions in SrDy2O4
• Existence of a Thermodynamic Spin-Glass Phase in the Zero-Concentration Limit of Anisotropic Dipolar Systems
• Probing many-body localization in a disordered quantum magnet
• Non-monotonic residual entropy in diluted spin ice: a comparison between Monte Carlo simulations of diluted dipolar spin ice models and experimental results
• Numerical linked cluster expansions for inhomogeneous systems
• Phase diagram with enhanced spin-glass region of mixed Ising / XY magnets LiHo${}_x$Er${}_{1-x}$F${}_4$
• Evolution of spin relaxation processes in LiY${}_{1-x}$Ho${}_x$F${}_4$ with increasing x studied via AC-susceptibility and muon spin relaxation
• Exact Solution for the Transverse Field Sherrington-Kirkpatrick Spin Glass Model with Continuous-Time Quantum Monte Carlo Method
• Dynamical Quantum Phase Transitions in presence of a spin bath
• Nonlinear susceptibility of a quantum spin glass under uniform transverse and random longitudinal magnetic fields
• The Effect of Intrinsic Quantum Fluctuations on the Phase Diagram of Anisotropic Dipolar Magnets