Strong Spin–Charge Coupling and Its Manifestation in the Quasiparticle Structure, Cooper Instability, and Electromagnetic Properties of Cuprates

Journal Article · Sat Jun 15 04:00:00 EDT 2019 · Journal of Experimental and Theoretical Physics

DOI:https://doi.org/10.1134/S1063776119050078· OSTI ID:22917730

Dzembisashvili, D. M.; Korovushkin, M. M.; Komarov, K. K. ^[1]; Barabanov, A. F. ^[2]

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1. Kirensky Institute of Physics, Federal Research Center “Krasnoyarsk Scientific Center,” Siberian Branch, Russian Academy of Sciences (Russian Federation)
2. Vereshchagin Institute of High-Pressure Physics, Russian Academy of Sciences (Russian Federation)

The Fermi excitation spectrum, the problem of Cooper instability, and the Londons magnetic field penetration depth in cuprate superconductors are considered using the unified conception based on accounting for the strong coupling between the spin of copper ions and holes at oxygen ions. This coupling leads to strong renormalization of the primary spectrum of oxygen holes with the formation of spin-polaron quasiparticles. Analysis of Cooper instability performed using the spin-polaron concept for different channels has shown that only the superconducting d-wave pairing occurs in the ensemble of spin-polaron quasiparticles, and there are no solutions corresponding to the s-wave pairing. It has been demonstrated that the superconducting d-wave pairing is not suppressed by the Coulomb repulsion of holes located at neighboring oxygen ions. This effect is due to peculiarities in the crystallographic structure of the CuO{sub 2} plane and the aforementioned strong spin–fermion coupling. As a result, such interaction of holes is omitted in the kernel of the integral equation for the superconducting order parameter with the d-wave symmetry. It has been shown the Hubbard repulsion of holes and their interaction for the second coordination sphere of the oxygen sublattice for actual intensities of the interaction do not suppress the d-wave type of superconductivity. For the spin-polaron ensemble, we have analyzed the dependence of the Londons magnetic field penetration depth on the temperature and hole concentration. It has been established that the peculiarities of this dependence are closely related to specific features of the spin-polaron spectrum.

• OSTI ID: 22917730
• Journal Information: Journal of Experimental and Theoretical Physics, Journal Name: Journal of Experimental and Theoretical Physics Journal Issue: 6 Vol. 128; ISSN JTPHES; ISSN 1063-7761
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COPPER IONS
COPPER OXIDES
COULOMB FIELD
CRYSTALLOGRAPHY
CUPRATES
D WAVES
HOLES
INSTABILITY
INTERACTIONS
MAGNETIC FIELDS
OXYGEN IONS
POLARONS
S WAVES
SPECTRA
SPIN
STRONG-COUPLING MODEL
SUPERCONDUCTIVITY