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تسجيل مستخدم جديدMeasurement and analysis of the Hall effect of A-Fe$_2$As$_2$ single crystals with A = Ba, Ca or Sr
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We report measurements of the Hall coefficient $R_H$ for single crystals of AFe$_2$As$_2$ with $A = Ba, Ca$ or $Sr$ which are the anti-ferromagnetic parent compounds of some high temperature pnictide superconductors. We show that $R_H$ of Sr-122 is consistent with high field quantum oscillation data. Our $R_H(T)$ data can also be used to estimate values of the spin density wave gap, giving $Delta_{SDW}(0) = 710pm 70$ K for Sr-122 and $435pm 20$ K for Ba-122.
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We have studied the electronic and magnetic structures of the ternary iron arsenides AFe$_2$As$_2$ (A = Ba, Ca, or Sr) using the first-principles density functional theory. The ground states of these compounds are in a collinear antiferromagnetic ord
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