اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدA High-Tc Mechanism of Iron Pnictide Superconductivity due to Cooperation of Ferro-orbital and Antiferromagnetic Fluctuations
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The electronic states and superconductivity in iron pnictides are studied on the basis of the 16 band $d$-$p$ model which includes both the onsite Coulomb interaction between Fe $d$ electrons and the intersite one between Fe $d$ and pnictogen $p$ electrons. The model well accounts for experimentally observed two fluctuations: the $d$-$d$ interaction-enhanced antiferromagnetic (AFM) fluctuation and the $d$-$p$ interaction-enhanced ferro-orbital (FO) fluctuation responsible for the $C_{66}$ elastic softening. The AFM fluctuation induces the repulsive pairing interaction for $bm{q}sim bm{Q}_{rm AF}$ while the FO does the attractive one for $bm{q}sim bm{0}$ resulting in the $s_{pm}$-wave superconductivity where the two fluctuations cooperatively enhance the superconducting transition temperature $T_{c}$ without any competition by virtue of the $bm{q}$-space segregation.
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Cooper pairing in the iron-based high-Tc superconductors is often conjectured to involve bosonic fluctuations. Among the candidates are antiferromagnetic spin-fluctuations and d-orbital fluctuations amplified by phonons. Any such electron-boson inter
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This paper has been withdrawn by the author due to some experimental mistakes. In this paper, we reported that C66, C44 and (C11-C12)/2 show remarkable softening toward the structural transition temperature TS. The data reported in this paper were ac
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