Flux phase as a dynamic Jahn-Teller phase: Berryonic matter in the cuprates

Article

关键词: HIGH-TEMPERATURE SUPERCONDUCTORS;    HIGH-TC SUPERCONDUCTIVITY;    TIGHT-BINDING MODEL;    2-DIMENSIONAL HUBBARD-MODEL;    ELECTRON-PHONON INTERACTION;    SPIN-DENSITY WAVES;    RIGID-UNIT MODES;    HIGH-T(C) SUPERCONDUCTIVITY;    PEIERLS INSTABILITY;    STRIPE CORRELATIONS;   

DOI  :  10.1103/PhysRevB.66.024506

来源: SCIE

【 摘 要 】

There is considerable evidence for some form of charge ordering on the hole-doped stripes in the cuprates, mainly associated with the low-temperature tetragonal phase, but with some evidence for either charge-density waves or a flux phase, which is a form of dynamic charge-density wave. These three states form a pseudospin triplet, demonstrating a close connection with the Exe dynamic Jahn-Teller (DJT) effect, suggesting that the cuprates constitute a form of Berryonic matter. This in turn suggests a new way of looking at the DJT effect: we provide an interpretation in terms of abstract operator algebra, demonstrating (1) a purely electronic DJT effect and (2) a generalization of the DJT effect applying to a wide category of competing instabilities. A simple model of the Cu-O bond stretching phonons allows an estimate of electron-phonon coupling for these modes, explaining why the half breathing mode softens so much more than the full oxygen breathing mode. The anomalous properties of O2- provide a coupling (correlated hopping) which acts to stabilize density wave phases.

【 授权许可】

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