Charge instabilities due to breathing mode electron-phonon coupling in the single-band Hubbard theory for cuprate superconductors

Conference · Thu Aug 01 00:00:00 EDT 1991

OSTI ID:5160436

Fedro, A J ^[1]; Schuettler, H B ^[2]

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1. Northern Illinois Univ., De Kalb, IL (United States). Dept. of Physics Argonne National Lab., IL (United States)
2. Georgia Univ., Athens, GA (United States). Center for Simulational Physics

We study possible phonon-driven charge instabilities in the cuprate superconductors within the frame-work of a single-band two- dimensional extended Hubbard electron system with on-site electron-phonon (EP) coupling to the in- and out-of-plane oxygen breathing mode motion. We identify the relevant competing phases in the ionic (t=0) limit and predict the existence of a novel, dopant induced, coexistent charge density wave (CDW) and spin density wave (SDW) ordered state near {1/4}-filling, with a CDW {radical}{bar 2} {times} {radical}{bar 2}{minus} and an SDW 2{times}2-supercell, respectively. We then develop a systematic strong-coupling expansion, to 2nd order in the delocalization energy t, which allows us to study the effect of finite t on the relative stability of the competing phases. We stress that, a consequence of the Franck-Condon principle, even a very strong EP coupling will have only a small effect on the observable electronic and spin excitations in the undoped, insulating groundstate phase of the cuprate parent compounds. Strong EP coupling will manifest itself only in the presence of doping. 6 refs.

• Research Organization: Argonne National Lab., IL (United States)
• Sponsoring Organization: USDOE; National Science Foundation (NSF); GAU; USDOE, Washington, DC (United States); National Science Foundation, Washington, DC (United States); Georgia Univ., Athens, GA (United States)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5160436
• Report Number(s): ANL/CP-73399; CONF-9107143-3; ON: DE91018538; CNN: DMR-8913878
• Resource Relation: Conference: International workshop on electronic properties and mechanisms in high-T sub c superconductors, Tsukuba (Japan), 29-31 Jul 1991
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CUPRATES
ELECTRON-PHONON COUPLING
FRANCK-CONDON PRINCIPLE
HIGH-TC SUPERCONDUCTORS
OXYGEN
COPPER COMPOUNDS
COUPLING
ELEMENTS
NONMETALS
OXYGEN COMPOUNDS
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS
360204* - Ceramics
Cermets
& Refractories- Physical Properties
656100 - Condensed Matter Physics- Superconductivity