Superconductivity-Induced Anomalies in the Spin Excitation Spectra of Underdoped YBa2Cu3O61x
نویسندگان
چکیده
Polarized and unpolarized neutron scattering have been used to determine the effect of superconductivity on the magnetic excitation spectra of YBa 2Cu 3O 6.5 sTc 52 Kd and YBa 2Cu 3O 6.7 sTc 67 Kd. Pronounced enhancements of the spectral weight centered around 25 and 33 meV, respectively, are observed below Tc 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 YBa2Cu 3O 7. [S0031-9007(96)02291-0]
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