Pairing fluctuations in a one-dimensional copper oxide model

Journal Article · Sun Jan 01 04:00:00 EST 1995 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.51.553· OSTI ID:7060892

Stechel, E B ^[1]; Sudbo, A ^[2]; Giamarchi, T ^[3]; Varma, C M ^[4]

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1. Sandia National Laboratories, MS-0345, Albuquerque, New Mexico 87185 (United States)
2. Institutt for Fysikk, Norges Tekniske Hogskole, 7034 Trondheim-NTH (Norway)
3. Laboratoire de Physique des Solides, Universitee Paris-Sud, 91405 Orsay (France)
4. AT T Bell Laboratories, Murray Hill, New Jersey 07974 (United States)

The exact ground-state energy [ital E][sub 0]([Phi]) is calculated for a one-dimensional copper-oxide model defined on a ring of finite length [ital L], threaded by an external flux [Phi]. It includes on-site and nearest-neighbor intersite Coulomb repulsion [ital V], as well as a nonzero bare oxide'' gap [Delta][sub 0] between the orbitals in the unit cell. The correlation exponent [ital K][sub [rho]] of the corresponding low-energy Hamiltonian shows that singlet (extended [ital s]-wave) superconductivity has the most rapidly diverging susceptibility as [ital T][r arrow]0 ([ital K][sub [rho]][gt]1). This superconducting phase is located close to a phase-separation instability of the model, indicated by [ital K][sub [rho]][r arrow][infinity]. Longer range of the Coulomb interaction tends to frustrate phase separation, enhances the range of [ital V] for which [ital K][sub [rho]][gt]1, and slightly broadens the regime of [ital V] where 1[lt][ital K][sub [rho]][lt][infinity].

• DOE Contract Number: AC04-76DP00789
• OSTI ID: 7060892
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 51:1; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

665411* -- Basic Superconductivity Studies-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COPPER COMPOUNDS
CUPRATES
ENERGY LEVELS
FLUCTUATIONS
GROUND STATES
HIGH-TC SUPERCONDUCTORS
INTERACTIONS
OXYGEN COMPOUNDS
PAIRING INTERACTIONS
PARTIAL WAVES
S WAVES
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS
VARIATIONS