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تسجيل مستخدم جديدBulk Nature of Layered Perovskite Iridates beyond the Mott Scenario : An Approach from Bulk Sensitive Photoemission Study
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We present genuine bulk Ir 5d jeff states of layered perovskite iridates obtained by hard-x-ray photoemission spectroscopy (HAXPES) with s- and p-polarized lights. HAXPES spectra of Sr2IrO4 and Ba2IrO4 are well reproduced by the quasi-particle densities of states calculated by the local density approximation with dynamical mean-field theory (LDA+DMFT). It is demonstrated that the insulating nature of the iridates is triggered by antiferromagnetic correlation (Slater type) combined with electron correlation (Mott type). The extremely-low-energy bulk-sensitive photoemission spectroscopy reveals bad metallic states in the paramagnetic phase of the iridates, suggesting strongly renormalized metallic states above the Neel temperature as predicted by the LDA+DMFT.
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%auto-ignore This paper has been withdrawn by the authors because its results have been superceded by new experimental data and new theory presented in S.-K. Mo et al., cond-mat/0212110.
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