1. High pressure synthesis and characterization of the pyrochlore Dy2Pt2O7: A new spin ice material*
- Author
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Xiang Li, Pei-Jie Sun, Zhiling Dun, Haidong Zhou, Jinguang Cheng, Jianshi Zhou, Yunqi Cai, and Qi Cui
- Subjects
Spin ice ,Materials science ,Chemical physics ,High pressure ,Pyrochlore ,engineering ,General Physics and Astronomy ,engineering.material ,Characterization (materials science) - Abstract
The cubic pyrochlore Dy2Pt2O7 was synthesized under 4 GPa and 1000 °C and its magnetic and thermodynamic properties were characterized by DC and AC magnetic susceptibility and specific heat down to 0.1 K. We found that Dy2Pt2O7 does not form long-range magnetic order, but displays characteristics of canonical spin ice such as Dy2Ti2O7, including (1) a large effective moment 9.64 μ B close to the theoretical value and a small positive Curie–Weiss temperature θ CW = +0.77 K signaling a dominant ferromagnetic interaction among the Ising spins; (2) a saturation moment ∼4.5 μ B being half of the total moment due to the local 〈111〉 Ising anisotropy; (3) thermally activated spin relaxation behaviors in the low (∼1 K) and high (∼20 K) temperature regions with different energy barriers and characteristic relaxation time; and most importantly, (4) the presence of a residual entropy close to Pauling’ estimation for water ice.
- Published
- 2020
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