Quantum symmetries induced by phonons in the Hubbard model

Journal Article · Mon Mar 14 04:00:00 EST 1994 · Physical Review Letters; (United States)

DOI:https://doi.org/10.1103/PhysRevLett.72.1730· OSTI ID:5013326

Montorsi, A; Rasetti, M ^[1]

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1. Theory Division, Los Alamos National Laboratories, Los Alamos, New Mexico 87545 (United States) Dipartimento di Fisica and Unita Istituto Nazionale di Fisica della Materia, Politecnico di Torino, I-10129 Torino (Italy)

We show how the addition of a phonon field to the Hubbard model deforms the [ital superconducting] su(2) part of the global symmetry Lie algebra su(2)[direct product]su(2)/[ital openZ][sub 2], holding at half filling for the customary model, into a [ital quantum] [su(2)][sub [ital q]] symmetry, holding for a filling which depends on the electron-phonon interaction strength. Such symmetry originates in the feature that in the presence of phonons the hopping amplitude turns out to depend on the coupling strength. The states generated by resorting to this [ital q] symmetry exhibit both off-diagonal long-range order and pairing.

• OSTI ID: 5013326
• Journal Information: Physical Review Letters; (United States), Journal Name: Physical Review Letters; (United States) Vol. 72:11; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

665411* -- Basic Superconductivity Studies-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALGEBRA
COUPLING
CRYSTAL MODELS
ELECTRON-PHONON COUPLING
HIGH-TC SUPERCONDUCTORS
HUBBARD MODEL
INTERACTIONS
MATHEMATICAL MODELS
MATHEMATICS
PAIRING INTERACTIONS
SUPERCONDUCTORS
SYMMETRY GROUPS