Tuning orbital-selective correlation effects in superconducting Rb$_{0.75}$Fe$_{1.6}$Se$_{2-z}$S$_z$

Zhe Wang; V. Tsurkan; M. Schmidt; A. Loidl; J. Deisenhofer

doi:10.1103/PhysRevB.93.104522

paper

Tuning orbital-selective correlation effects in superconducting Rb $_{0.75}$ Fe $_{1.6}$ Se $_{2 - z}$ S $_{z}$

arXiv:1506.04614 · doi:10.1103/PhysRevB.93.104522

Abstract

We report on terahertz time-domain spectroscopy on superconducting and metallic iron chalcogenides Rb $_{0.75}$ Fe $_{1.6}$ Se $_{2 - z}$ S $_{z}$ . The superconducting transition is reduced from $T_{c} =$ 32 K ( $z = 0$ ) to 22 K ( $z = 1.0$ ), and finally suppressed ( $z = 1.4$ ) by isoelectronic substitution of Se with S. Dielectric constant and optical conductivity exhibit a metal-to-insulator transition associated with an orbital-selective Mott phase. This orbital-selective Mott transition appears at higher temperature $T_{m e t}$ with increasing sulfur content, identifying sulfur substitution as an efficient parameter to tune orbital-dependent correlation effects in iron-chalcogenide superconductors. The reduced correlations of the $d_{x y}$ charge carriers can account for the suppression of the superconductivity and the pseudogap-like feature between $T_{c}$ and $T_{m e t}$ that was observed for $z = 0$ .

6 pages, 4 figures

Tuning orbital-selective correlation effects in superconducting Rb $_{0.75}$ Fe $_{1.6}$ Se $_{2 - z}$ S $_{z}$

Abstract

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Tuning orbital-selective correlation effects in superconducting Rb0.75​Fe1.6​Se2−z​Sz​

Abstract

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Cited by in corpus (4)

Tuning orbital-selective correlation effects in superconducting Rb $_{0.75}$ Fe $_{1.6}$ Se $_{2 - z}$ S $_{z}$