Superconductivity-Induced Anomalies in the Spin Excitation Spectra of Underdoped YBa_2 Cu_3 O_{6+x}

H. F. Fong; B. Keimer; D. L. Milius; I. A. Aksay

doi:10.1103/physrevlett.78.713

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Superconductivity-Induced Anomalies in the Spin Excitation Spectra of Underdoped YBa_2 Cu_3 O_{6+x}

H. F. Fong·B. Keimer·D. L. Milius·I. A. Aksay

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Abstract

Polarized and unpolarized neutron scattering has been used to determine the effect of superconductivity on the magnetic excitation spectra of YBa_2 Cu_3 O_{6.5} (T_c = 52K) and YBa_2 Cu_3 O_{6.7} (T_c = 67K). Pronounced enhancements of the spectral weight centered around 25 meV and 33 meV, respectively, are observed below T_c in both crystals, compensated predominantly by a loss of spectral weight at higher energies. The data provide important clues to the origin of the 40 meV magnetic resonance peak in YBa_2 Cu_3 O_7.

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H. F. Fong, B. Keimer, D. L. Milius, I. A. Aksay. 1996-12-11. Superconductivity-Induced Anomalies in the Spin Excitation Spectra of Underdoped YBa_2 Cu_3 O_{6+x}. https://doi.org/10.1103/physrevlett.78.713

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