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تسجيل مستخدم جديدMagnetic short and long range order in PbFe$_{1/2}$Ta$_{1/2}$O$_{3}$
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PbFe$_{1/2}$Ta$_{1/2}$O$_{3}$ (PFT) belongs to the family of PbB$_{x}$B$_{1-x}$O$_{3}$ which have inherent chemical disorder at the B-site. Due to this disorder, a complex magnetic phase diagram is expected in the material. In this paper, we report experimental results of magnetic properties in PFT through macroscopic characterization, neutron scattering and M{o}ssbauer spectroscopy techniques. With these results we show for the first time that PbFe$_{1/2}$Ta$_{1/2}$O$_{3}$ behaves very similar to PbFe$_{1/2}$Nb$_{1/2}$O$_{3}$, i.e, it undergoes AF transition at 153 K and has a spinglass transition at 10 K, below which the antiferromagnetism coexists with spinglass. We suggest that the mechanism which is responsible for such a non-trivial ground state can be explained by a speromagnet-like spin arrangement similar to the one proposed for PbFe$_{1/2}$Nb$_{1/2}$O$_{3}$.
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