Phase diagram with an enhanced spin-glass region of the mixed Ising–XYmagnet LiHoxEr1−x<

Abstract

We present the experimental phase diagram of LiHo x Er 1-x F 4 , a dilution series of dipolar-coupled model magnets. The phase diagram was determined using a combination of ac susceptibility and neutron scattering. Three unique phases in addition to the Ising ferromagnet LiHoF 4 and the XY antiferromagnet LiErF 4 have been identified. Below x = 0.86, an embedded spin-glass phase is observed, where a spin glass exists within the ferromagnetic structure. Below x = 0.57, an Ising spin glass is observed consisting of frozen needlelike clusters. For x ∼ 0.3-0.1, an antiferromagnetically coupled spin glass occurs. A reduction of T C (x) for the ferromagnet is observed which disobeys the mean-field predictions that worked for LiHo x Y 1-x F 4 .

Nonequilibrium hysteresis and spin relaxation in the mixed-anisotropy dipolar-coupled spin-glassLiHo0.5Er0.5F4

“…1(d). The ZFC-FC splitting in M (T ) and the peak in χ (T ), which is suppressed rapidly in a field, are consistent with the reported mixed Ising-XY SG phase [14]. Fig.…”

“…Typical SGs also show nonequilibrium relaxation in both the thermoremanent magnetization, the magnetization acquired when field cooled (FC), and the isothermal remanent magnetization, the instantaneous magnetization obtained by applying a field following zero-field cooling (ZFC) [9,10]. Examples of more exotic behavior include the frequency dependent effects observed in LiHo 0.045 Y 0.955 F 4 [11], which are only seen when the sample is weakly coupled to the thermal bath [12,13].LiHo 0.5 Er 0.5 F 4 exhibits a low-temperature SG state below T g ∼ 0.4 K, which can be interpreted as coexistence of both Ising and XY SGs [14]. The bulk of the magnetic properties appear to come from the Ising Ho 3+ spins which, according to neutron scattering, form small clusters highly elongated along the Ising axis and show no sign of long-range order (LRO).…”

“…LiHo 0.5 Er 0.5 F 4 exhibits a low-temperature SG state below T g ∼ 0.4 K, which can be interpreted as coexistence of both Ising and XY SGs [14]. The bulk of the magnetic properties appear to come from the Ising Ho 3+ spins which, according to neutron scattering, form small clusters highly elongated along the Ising axis and show no sign of long-range order (LRO).…”

“…The configuration was used in order to have the largest possible Q range, which was constrained by the small magnet window. This technique allows us to probe the distinctive butterfly-shaped scattering which is observed around ferromagnetic Bragg peak (BP) positions [14] due to short range correlations in this dipolar-coupled system.…”

Metastable skyrmion lattices governed by magnetic disorder and anisotropy in β -Mn-type chiral magnets

“…x 7 displaying reentrant spin-glass behavior [46] as similarly reported for a number of ferromagnets [47][48][49][50][51][52], antiferromagnets [53,54], and helimagnets [55] with chemical and magnetic disorder. The spin-glass nature was confirmed by previous frequency-dependent ac susceptibility measurements for Co 7 Zn 7 Mn 6 (T c ∼ 160 K, T g ∼ 30 K) [29,31,56].…”