Critical behavior in single-crystallineLa0.67Sr0.33CoO3

Abstract

The critical behavior of La 0.67 Sr 0.33 CoO 3 single crystal has been investigated from the bulk magnetization measurements around the Curie temperature ͑T C ͒. The detailed analysis of the magnetization indicates the occurrence of a continuous ferromagnetic to paramagnetic phase transition at 223.0 K. The critical exponents ␤ = 0.361Ϯ 0.007, ␥ = 1.31Ϯ 0.001, and ␦ = 4.64Ϯ 0.01 characterizing this second order phase transition, have been estimated using different techniques such as the Kouvel-Fisher plot, the Arrott-Noaks plot, and critical isotherm analysis. With these values of T C , ␤, and ␥, one can scale the magnetization below and above T C following a single equation of state. The consistency in the values of the critical exponents obtained from different methods and the well-obeyed scaling behavior confirm that the calculated exponents are unambiguous and purely intrinsic to the system. These values of the exponents match well with those theoretically predicted for the three-dimensional Heisenberg model with nearest-neighbor interaction.

Critical phenomenon of the layered chiral helimagnetic YbNi3Al9

“…Figure 7(b) shows the m(h) curves on loglog scale for YbNi 3 Al 9 . Based on the scaling equation, all m(h) curves at different temperatures should collapse into two independent branches for T>T C and T<T C respectively, even those in lower field region [58,59]. As shown in figure 7(b), m(h) curves for T>T C and T<T C collapse onto two independent branches in the higher field region, which is in agreement with the scaling equation.…”

Evidence of ferromagnetic short-range correlations in cubic La1−xSrxMnO3−δ(x = 0.80, 0.85) above antiferromagnetic ordering

“…An experimental µ eff more than the theoretical µ eff corresponds to magnetic polarons with FM interaction and vice versa. Furthermore, the χ −1 ( T ) below T FMC shows a sharp down turn, which is considered to be the hallmark of stabilization of interacting FM polarons in a PM matrix and rejects the possibility of smeared phase transition , which will show an upturn in χ −1 ( T ) curves. The oxygen off‐stoichiometric samples show similar χ −1 ( T ) behavior as that of stoichiometric ones with only a few Kelvin shifts in T FMC accompanied by the weakening of AFM correlations.…”

Study of magnetic entropy and ESR in ferromagnet CuCr2Te4

“…5(b). This indicates that critical spin fluctuation [36,37] arises at T n , leading to the deviation from CW linear of 1/DIN-T (1/M-T). With further cooling below T C , the rapidly enhanced spinorbit coupling leads to the rapid increase of DH pp .…”