Theory of dynamic spin susceptibility in terms of the t-J-V model: Comparison with neutron scattering data for Pr{sub 0.88}LaCe{sub 0.12}CuO{sub 4-x} and La{sub 2-x}Sr{sub x}CuO{sub 4}

Journal Article · Thu Jan 15 00:00:00 EST 2009 · Journal of Experimental and Theoretical Physics

DOI:https://doi.org/10.1134/S1063776109010087· OSTI ID:21246970

Eremin, I M ^[1]; Eremin, M V ^[2]

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1. Max-Plank Institute for Physics of Complex Systems (Germany)
2. Kazan State University (Russian Federation)

A formula for the dynamic spin susceptibility is derived in terms of the t-J-V model. This formula makes it possible to explain the main features of recent experiments on neutron scattering in the electron-doped superconductor Pr{sub 0.88}LaCe{sub 0.12}CuO{sub 4-x}. In particular, the proposed theory reproduces well a V-shaped relief in the frequency behavior of the imaginary part {chi}''(Q, {omega}) of the susceptibility of the Pr{sub 0.88}LaCe{sub 0.12}CuO{sub 4-x} compound in the vicinity of the wave vector Q = ({pi},{pi}) and the scaling behavior of the position of the maxima in the dependence of the function {chi}''(Q, {omega}) T on the quantity {omega}/T. The magnetism of the high-temperature superconductors is dual. These materials contain charge carriers, on the one hand, and localized spins in the copper ion sublattice, on the other hand. Both these systems are strongly coupled to each other. The mode of collective oscillations is common. The magnetism of localized spins 'freezes' with the appearance of the superconducting gap. The recently revealed double-peak structure of the imaginary part {chi}''(Q, {omega}) of the susceptibility in superconductors of the La{sub 1.84}Sr{sub 0.16}CuO{sub 4} type is explained. The low-frequency absorption peak is located within the superconducting gap and interpreted as a manifestation of the branch of spin excitons, and the high-frequency absorption peak predominantly corresponds to renormalized collective oscillations of localized spins.

• OSTI ID: 21246970
• Journal Information: Journal of Experimental and Theoretical Physics, Vol. 108, Issue 1; Other Information: DOI: 10.1134/S1063776109010087; Copyright (c) 2009 Pleiades Publishing, Ltd; Country of input: International Atomic Energy Agency (IAEA); ISSN 1063-7761
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ABSORPTION
CERIUM COMPOUNDS
CHARGE CARRIERS
COMPARATIVE EVALUATIONS
COPPER IONS
CUPRATES
DOPED MATERIALS
ELECTRONS
EXCITONS
HIGH-TC SUPERCONDUCTORS
LANTHANUM COMPOUNDS
MAGNETIC SUSCEPTIBILITY
MAGNETISM
NEUTRON DIFFRACTION
OSCILLATIONS
PRASEODYMIUM COMPOUNDS
SPIN
STRONTIUM COMPOUNDS