Double exchange manganites;
Second order transition;
Critical phenomena;
EQUATION-OF-STATE;
CRITICAL EXPONENTS;
CRITICAL-BEHAVIOR;
ELECTRICAL-PROPERTIES;
MAGNETIC-BEHAVIOR;
NICKEL;
D O I:
10.1016/j.solidstatesciences.2012.03.012
中图分类号:
O61 [无机化学];
学科分类号:
070301 ;
081704 ;
摘要:
We studied the critical phenomena of perovskite-manganite compound Pr0.6Sr0.4MnO3 around its Curie temperature. Experimental results based on magnetic measurements using Banerjee criterion revealed that the sample exhibits the second-order paramagnetic-ferromagnetic transition. It is found that the critical behaviour analysis and Kouvel Fisher method show that the 3D- Heisenberg model is the best one to describe the critical phenomena around the critical point. Critical exponents beta = 0.3785(6) and gamma = 1.304(12) at T-C = 320 K are obtained. The critical exponent delta = 4.7183(2) is determined separately from the isothermal magnetization at T. These critical exponents fulfil the Widom scaling relation delta = 1 + gamma/beta. Based on the critical exponents, the magnetization-field-temperature (M-H-T) data around T-C collapses into two curves obeying the single scaling equation M(H,epsilon) = vertical bar epsilon vertical bar(beta)integral +/-(H/vertical bar epsilon vertical bar(beta+gamma)) with epsilon = (T-T-C)/T-C is the reduced temperature. (C) 2012 Elsevier Masson SAS. All rights reserved.