The Persistence of High-Frequency Spin Fluctuations in Overdoped La$_{2-x}$Sr$_{x}$CuO$_{4}$ ($x$=0.22)

O. J. Lipscombe; S. M. Hayden; B. Vignolle; D. F. McMorrow; T. G. Perring

doi:10.1103/physrevlett.99.067002

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arXiv · 0706.4464

The Persistence of High-Frequency Spin Fluctuations in Overdoped La$_{2-x}$Sr$_{x}$CuO$_{4}$ ($x$=0.22)

O. J. Lipscombe·S. M. Hayden·B. Vignolle·D. F. McMorrow·T. G. Perring

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Abstract

We report a detailed inelastic neutron scattering study of the collective magnetic excitations of overdoped superconducting La1.78Sr0.22CuO4 for the energy range 0-160 meV. Our measurements show that overdoping suppresses the strong response present for optimally doped La2-xSrxCuO4 which is peaked near 50 meV. The remaining response is peaked at incommensurate wavevectors for all energies investigated. We observe a strong high-frequency magnetic response for E >= 80 meV suggesting that significant antiferromagnetic exchange couplings persist well into the overdoped part of the cuprate phase diagram.

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O. J. Lipscombe, S. M. Hayden, B. Vignolle, D. F. McMorrow, T. G. Perring. 2007-06-29. The Persistence of High-Frequency Spin Fluctuations in Overdoped La$_{2-x}$Sr$_{x}$CuO$_{4}$ ($x$=0.22). https://doi.org/10.1103/physrevlett.99.067002

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