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A Comparison of the High-Frequency Magnetic Fluctuations in Insulating and Superconducting La2-xSrxCuO4

S. M. Hayden·G. Aeppli·H. A. Mook·T. G. Perring·T. E. Mason·S-W. Cheong·Z. Fisk
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Abstract

Inelastic neutron scattering performed at a spallation source is used to make absolute measurements of the dynamic susceptibility of insulating La2CuO4 and superconducting La2-xSrxCuO4 over the energy range 15<EN<350 meV. The effect of Sr doping on the magnetic excitations is to cause a large broadening in wavevector and a substantial change in the spectrum of the local spin fluctuations. Comparison of the two compositions reveals a new energy scale of 22 meV in La1.86Sr0.14CuO4.

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S. M. Hayden, G. Aeppli, H. A. Mook, T. G. Perring, T. E. Mason, S-W. Cheong, Z. Fisk. 1996-11-22. A Comparison of the High-Frequency Magnetic Fluctuations in Insulating and Superconducting La2-xSrxCuO4. https://doi.org/10.1103/physrevlett.76.1344

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