Four-band model for oxygen holes in copper oxide superconductors. I. Quasiparticles

Journal Article · Fri May 01 00:00:00 EDT 1992 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.45.9915· OSTI ID:7297541

Klein, L; Aharony, A ^[1]

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1. School of Physics and Astronomy, Beverly and Raymond Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978 (Israel)

All the high-temperature superconductors have copper oxide planes with strong antiferromagnetic correlations. In many of these, the charge is carried by quasiparticles which are based on holes that move on the oxygen ions. We study the effect of the antiferromagnetic background of the Cu spins in the CuO{sub 2} planes on the spectrum of the mobile quasiparticles. We consider several possible quasiparticles, which involve the spin of the hole and the spins of the two neighboring copper ions. For each quasiparticle we obtain, using tight-binding methods, four energy bands. We find that the favored charge carrier is a spin 1/2 quasiparticle. The minimum of the lowest energy band is at the points {bold k}=(0,{plus minus}{pi}/2{ital {tilde a}}) and {bold k}=({plus minus}{pi}/2{ital {tilde a}},0), where the {ital x} and {ital y} directions are along the nearest-neighbors oxygen-oxygen bonds (of length {ital {tilde a}}) in the CuO{sub 2} plane. The effective mass is less than 3.7{ital m}{sub {ital e}}, in good agreement with measurements of the London penetration depth for La{sub 2{minus}{ital x}}Sr{sub {ital x}}CuO{sub 4}. It is also consistent with these measurements for the Bi and Tl compounds. However, we obtain conflicting results for YBa{sub 2}Cu{sub 3}O{sub 6+{ital y}}, possibly due to the fact that the CuO chains also superconduct.

• OSTI ID: 7297541
• Journal Information: Physical Review, B: Condensed Matter; (United States), Vol. 45:17; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
HIGH-TC SUPERCONDUCTORS
HOLES
ANTIFERROMAGNETISM
COPPER OXIDES
CORRELATIONS
EFFECTIVE MASS
OXYGEN IONS
QUASI PARTICLES
CHALCOGENIDES
CHARGED PARTICLES
COPPER COMPOUNDS
IONS
MAGNETISM
MASS
OXIDES
OXYGEN COMPOUNDS
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS
665411* - Basic Superconductivity Studies- (1992-)