Magnetic entropy change and critical exponents in double perovskite Y2NiMnO6

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:368

Article

Sharma, G.¹  Tripathi, T. S.²  Saha, J.¹  Patnaik, S.¹ 

[1] Jawaharlal Nehru Univ, Sch Phys Sci, New Delhi 110067, India

[2] Inter Univ Accelerator Ctr, New Delhi 110067, India

关键词: Double perovskite;    Magnetocaloric effect;    Critical exponents;   

DOI  :  10.1016/j.jmmm.2014.05.035

来源: Elsevier

【 摘 要 】

We report the magnetic entropy change (Delta S-M) and the critical exponents in the double perovskite manganite Y2NiMnO6 with a tel to paramagnetic transition T-c similar to 85 K. For a magnetic field Change Delta H = 80 kOe, a maximum magnetic entropy change Delta S-M = -6.57 J/kg K is recorded around T-c. The critical exponents beta = 0.363 +/- 0.05 and gamma = 1.331 +/- 0.09 obtained from power law fitting to spontaneous magnetization M-s(T) and the inverse initial susceptibility chi(-1)(0)(T) satisfy well to values derived for a 3D-Heisenberg ferromagnet. The critical exponent delta=4.761 +/- 0.129 is determined from the isothermal magnetization at T-c. The scaling exponents corresponding to second order phase transition are consistent with the exponents from Kouvel-Fisher analysis and satisfy Widom's scaling relation delta=1 + (gamma/beta). Additionally, they also satisfy the single scaling equation M(H, epsilon) = e(beta)f +/- (H/e(beta+gamma)) according to which the magnetization-field-temperature data around T-c should collapse into two curves for temperatures below and above T-c. (C) 2014 Elsevier B.V. All rights reserved.

【 授权许可】

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