Influence of hole doping on spin dynamics in lightly doped copper oxide superconductors

Journal Article · Tue Nov 01 04:00:00 EST 1994 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.50.12935· OSTI ID:6836508

Onufrieva, F P ^[1]; Kushnir, V P ^[2]; Toperverg, B P ^[3]

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1. Laboratoire Leon Brillouin (CEA-CNRS), Centre d'Etudes Nucleaires de Saclay, 91191 Gif-sur-Yvette, Cedex (France)
2. Laboratoire Leon Brillouin (CEA-CNRS), Centre d'Etudes Nucleaires de Saclay, 91191 Gif-sur-Yvette, Cedex (France) Odessa University, Odessa 270000 (Ukraine)
3. Laboratoire Leon Brillouin (CEA-CNRS), Centre d'Etudes Nucleaires de Saclay, 91191 Gif-sur-Yvette, Cedex (France) Leningrad Nuclear Physics Institute, Gatchina, St. Petersburg 188350 (Russian Federation)

The spin dynamics in the doped antiferromagnetic (AF) state of high-[ital T][sub [ital c]] copper oxide superconductors has been investigated within the [ital t]-[ital t][prime]-[ital J] model. We have shown that a small number of doped holes affects the spin dynamics in the CuO[sub 2] planes so strongly that above a very small hole concentration, [ital n][sub [ital c]]=0.027, the two-dimensional (2D) AF ground state becomes unstable. We have also predicted a great change in the spin excitation spectrum for the doped AF state. For doping close to [ital n][sub [ital c]], a hydrodynamic regime of well-defined magnons collapses, and almost the whole region of long-wavelength spin waves corresponds to the overdamped regime of softened magnons in agreement with inelastic neutron-scattering experiments in YBa[sub 2]Cu[sub 3]O[sub 6]+[ital x] reported by Rossat-Mignod [ital et] [ital al]. Analyzing the imaginary part of the spin susceptibility [chi][prime][prime]([bold q],[omega]) we have discovered, in addition to the spin-wave part, also an incoherent band associated with electron-hole excitations. For the overdamped regime the energy ranges of coherent excitations and the incoherent band are overlapped and so it is impossible to separate them. Even for smallest [bold q], when the magnon peak and the band are separated, the relative contribution of the band increases with increasing [ital n] and dominates near the critical point.

• OSTI ID: 6836508
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 50:17; 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
ANTIFERROMAGNETISM
COPPER COMPOUNDS
CRYSTAL MODELS
CUPRATES
ENERGY LEVELS
GROUND STATES
HIGH-TC SUPERCONDUCTORS
HOLES
MAGNETIC PROPERTIES
MAGNETIC SUSCEPTIBILITY
MAGNETISM
MATHEMATICAL MODELS
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SPIN WAVES
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS