中国物理B ›› 2020, Vol. 29 ›› Issue (4): 47502-047502.doi: 10.1088/1674-1056/ab7b58

所属专题： Virtual Special Topic — Magnetism and Magnetic Materials

• SPECIAL TOPIC—Recent advances in thermoelectric materials and devices • 上一篇    下一篇

High pressure synthesis and characterization of the pyrochlore Dy2Pt2O7: A new spin ice material

Qi Cui(崔琦), Yun-Qi Cai(蔡云麒), Xiang Li(李翔), Zhi-Ling Dun(顿志凌), Pei-Jie Sun(孙培杰), Jian-Shi Zhou(周建十), Hai-Dong Zhou(周海东), Jin-Guang Cheng(程金光)   

  1. 1 Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
    2 School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China;
    3 Materials Science and Engineering Program, Mechanical Engineering, University of Texas at Austin, Austin, Texas 78712, USA;
    4 Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement of Ministry of Education, School of Physics, Beijing Institute of Technology, Beijing 100081, China;
    5 Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, USA;
    6 School of Physics, Georgia Institute of Technology, Atlanta, GA 30332, USA;
    7 Songshan Lake Materials Laboratory, Dongguan 523808, China
  • 收稿日期:2020-02-09 修回日期:2020-02-25 出版日期:2020-04-05 发布日期:2020-04-05
  • 通讯作者: Jin-Guang Cheng E-mail:jgcheng@iphy.ac.cn
  • 基金资助:
    Project supported by the National Key R&D Program of China (Grant No. 2018YFA0305700), the National Natural Science Foundation of China (Grant Nos. 11834016, 11874400, and 11921004), the Beijing Natural Science Foundation, China (Grant No. Z190008), the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences (Grant No. QYZDB-SSW-SLH013), and the CAS Interdisciplinary Innovation Team. ZLD and HDZ acknowledge the support of Grant No. NSF-DMR-1350002. JSZ acknowledges the support of NSF DMR Grant No. 1729588.

High pressure synthesis and characterization of the pyrochlore Dy2Pt2O7: A new spin ice material

Qi Cui(崔琦)1,2, Yun-Qi Cai(蔡云麒)1,2, Xiang Li(李翔)3,4, Zhi-Ling Dun(顿志凌)5,6, Pei-Jie Sun(孙培杰)1,2,7, Jian-Shi Zhou(周建十)3, Hai-Dong Zhou(周海东)5, Jin-Guang Cheng(程金光)1,2,7   

  1. 1 Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
    2 School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China;
    3 Materials Science and Engineering Program, Mechanical Engineering, University of Texas at Austin, Austin, Texas 78712, USA;
    4 Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement of Ministry of Education, School of Physics, Beijing Institute of Technology, Beijing 100081, China;
    5 Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, USA;
    6 School of Physics, Georgia Institute of Technology, Atlanta, GA 30332, USA;
    7 Songshan Lake Materials Laboratory, Dongguan 523808, China
  • Received:2020-02-09 Revised:2020-02-25 Online:2020-04-05 Published:2020-04-05
  • Contact: Jin-Guang Cheng E-mail:jgcheng@iphy.ac.cn
  • Supported by:
    Project supported by the National Key R&D Program of China (Grant No. 2018YFA0305700), the National Natural Science Foundation of China (Grant Nos. 11834016, 11874400, and 11921004), the Beijing Natural Science Foundation, China (Grant No. Z190008), the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences (Grant No. QYZDB-SSW-SLH013), and the CAS Interdisciplinary Innovation Team. ZLD and HDZ acknowledge the support of Grant No. NSF-DMR-1350002. JSZ acknowledges the support of NSF DMR Grant No. 1729588.

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摘要： The cubic pyrochlore Dy2Pt2O7 was synthesized under 4 GPa and 1000℃ 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 μB close to the theoretical value and a small positive Curie-Weiss temperature θCW=+0.77 K signaling a dominant ferromagnetic interaction among the Ising spins; (2) a saturation moment ～4.5 μB 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's estimation for water ice.

关键词: Dy2Pt2O7, pyrochlore oxide, spin ice, high-pressure synthesis

Abstract: The cubic pyrochlore Dy2Pt2O7 was synthesized under 4 GPa and 1000℃ 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 μB close to the theoretical value and a small positive Curie-Weiss temperature θCW=+0.77 K signaling a dominant ferromagnetic interaction among the Ising spins; (2) a saturation moment ～4.5 μB 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's estimation for water ice.

Key words: Dy2Pt2O7, pyrochlore oxide, spin ice, high-pressure synthesis

中图分类号:  (Quantized spin models, including quantum spin frustration)

  • 75.10.Jm
75.47.Lx (Magnetic oxides) 75.30.-m (Intrinsic properties of magnetically ordered materials) 75.30.Cr (Saturation moments and magnetic susceptibilities)