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تسجيل مستخدم جديدMagnetic moment evolution and spin freezing in doped BaFe$_{2}$As$_{2}$
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Fe-K$_{beta}$ X-ray emission spectroscopy measurements reveal an asymmetric doping dependence of the magnetic moments $mu_text{bare}$ in electron- and hole-doped BaFe$_{2}$As$_{2}$. At low temperature, $mu_text{bare}$ is nearly constant in hole-doped samples, whereas it decreases upon electron doping. Increasing temperature substantially enhances $mu_text{bare}$ in the hole-doped region, which is naturally explained by the theoretically predicted crossover into a spin-frozen state. Our measurements demonstrate the importance of Hunds coupling and electronic correlations, especially for hole-doped BaFe$_{2}$As$_{2}$, and the inadequacy of a fully localized or fully itinerant description of the 122 family of Fe pnictides.
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