Critical behavior study of the spin ordering transition in RVO3 (R = Ce, Pr, Nd, Sm, Gd, Er) by means of ac photopyroelectric calorimetry

JOURNAL OF ALLOYS AND COMPOUNDS

卷:703

Article

Oleaga, A.¹  Shvalya, V.^1,2  Liubachko, V.^1,2  Balakrishnan, G.³  Tung, L. D.^3,4  Salazar, A.¹ 

[1] Univ Pais Vasco UPV EHU, Dept Fis Aplicada 1, Escuela Tecn Super Ingn, Alameda Urquijo S-N, Bilbao 48013, Spain

[2] Uzhgorod Univ, Inst Solid State Phys & Chem, UA-88000 Uzhgorod, Ukraine

[3] Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England

[4] UCL, Dept Phys & Astron, Gower St, London WC1E 6BT, England

关键词: Orthovanadates;    Spin-ordering;    Phase transitions;    Critical behavior;    Universality class;   

DOI  :  10.1016/j.jallcom.2017.01.361

来源: Elsevier

【 摘 要 】

The thermal diffusivity of RVO3 single crystals (R - Ce, Pr, Nd, Sm, Gd, and Er) has been measured with an ac photopyroelectric calorimetry in the region in which the G-type orbital ordering and C-type spin ordering take place. Detailed measurements in the close neighbourhood of the spin ordering temperature have allowed to extract the critical parameter a and the critical ratio A(+)/A(-) for this transition. While the samples containing Ce, Nd, Sm and Er belong to the 3D-XY universality class (showing that the spins have an easy plane anisotropy), the sample with Gd, which is known to present a clear easy axis, belongs to the 3D-Ising class. Finally, PrVO3 shows an effective isotropic behavior, as the critical parameters found agree with the 3D-Heisenberg class. (C) 2017 Elsevier B.V. All rights reserved.

【 授权许可】

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