中国物理B ›› 2003, Vol. 12 ›› Issue (7): 792-795.doi: 10.1088/1009-1963/12/7/317

• • 上一篇    下一篇

Anomalous magnetostrictive effects in (La1-xTbx)2/3S1/3MnO3

张世远1, 吴坚2   

  1. (1)National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, China; (2)National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, China; Department of Mathematics and Physics, Hehai University, Nanjing 210098, China
  • 收稿日期:2002-11-06 修回日期:2003-01-22 出版日期:2003-07-16 发布日期:2005-03-16
  • 基金资助:
    Project supported by the National Key Project for Basic Research (Grant No G1999064508) and the Natural Science Foundation of China (Grant No 19890310(4)).

Anomalous magnetostrictive effects in (La1-xTbx)2/3S1/3MnO3

Wu Jian (吴坚)ab, Zhang Shi-Yuan (张世远)a   

  1. a National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, China; b Department of Mathematics and Physics, Hehai University, Nanjing 210098, China
  • Received:2002-11-06 Revised:2003-01-22 Online:2003-07-16 Published:2005-03-16
  • Supported by:
    Project supported by the National Key Project for Basic Research (Grant No G1999064508) and the Natural Science Foundation of China (Grant No 19890310(4)).

PDF (PC)

401

赞

摘要： A series of (La_{1-x}Tb_x)_{2/3}Sr_{1/3}MnO_3 polycrystalline samples has been studied by means of x-ray diffraction, magnetostriction, and thermal expansion measurements. It has been found that this series undergoes a phase transition from a rhombohedral to an orthorhombic form at the doping level x≈0.20 at room temperature accompanied by an anisotropic magnetostriction up to －50×10^{-6} under a magnetic field of 1T. The linear and volume magnetostrictions vary with chemical composition, even change sign. At T=80K, the magnetostrictions for the samples of x=0.20 and 0.40 exhibit different behaviours. The sample of x=0.20 has positive volume and linear magnetostrictions and a negative anisotropic magnetostriction, while the sample of x=0.40 has an opposite behaviour. The magnitude of volume magnetostriction for both the samples is essential (～10^{-4}) at T=80K under a magnetic field of 4T. We conclude that these anomalous effects are due to the charge delocalization and the structural phase transition between orthorhombic and rhombohedral forms induced by the applied magnetic field.

Abstract: A series of (La1-xTbx)2/3Sr1/3MnO3 polycrystalline samples has been studied by means of x-ray diffraction, magnetostriction, and thermal expansion measurements. It has been found that this series undergoes a phase transition from a rhombohedral to an orthorhombic form at the doping level x≈0.20 at room temperature accompanied by an anisotropic magnetostriction up to $－50×10^{-6}$ under a magnetic field of 1T. The linear and volume magnetostrictions vary with chemical composition, even change sign. At T=80K, the magnetostrictions for the samples of x=0.20 and 0.40 exhibit different behaviours. The sample of x=0.20 has positive volume and linear magnetostrictions and a negative anisotropic magnetostriction, while the sample of x=0.40 has an opposite behaviour. The magnitude of volume magnetostriction for both the samples is essential ($\sim10^{-4}$) at T=80K under a magnetic field of 4T. We conclude that these anomalous effects are due to the charge delocalization and the structural phase transition between orthorhombic and rhombohedral forms induced by the applied magnetic field.

Key words: magnetostriction, phase transition

中图分类号:  (Magnetomechanical effects, magnetostriction)

  • 75.80.+q
61.50.Ks (Crystallographic aspects of phase transformations; pressure effects) 81.30.Hd (Constant-composition solid-solid phase transformations: polymorphic, massive, and order-disorder) 75.47.Gk (Colossal magnetoresistance)