2007/08/31 by Erez Berg, T. H. Geballe, Theodore H. Geballe +1
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Magnetic and transport properties of perovskites and related materials #Physics of Superconductivity and Magnetism #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.76.214505
published as Phys. Rev. B 76, 214505 (2007) · 10 pages, 5 figures; Journal-ref. added
openalex publication_date 2007/12/12 · arxiv created 2008/01/29 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Superconductivity has recently been discovered in Pr2Ba4Cu7O_15\ensuremath-\ensuremathδ with a maximum Tc of about 15\phantom\rule0.3em0exK. Since the CuO planes in this material are believed to be insulating, it has been proposed that the superconductivity occurs in the double (or zigzag) CuO chain layer. On phenomenological grounds, we propose a theoretical interpretation of the experimental results in terms of a phase for the zigzag chain, labeled by C1S3∕2. This phase has a gap in the relative charge mode and a partial gap in the relative spin mode. It has gapless uniform charge and spin excitations and can have a divergent superconducting susceptibility, even for repulsive interactions. A microscopic model for the zigzag CuO chain is proposed, and on the basis of density matrix renormalization group and bosonization studies, we adduce evidence that supports our proposal.