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Effect of Nonmagnetic Impurities on the Magnetic Resonance Peak in YBa2Cu3O7

H. F. Fong·P. Bourges·Y. Sidis·L. P. Regnault·J. Bossy·A. Ivanov·D. L. Milius·I. A. Aksay·B. Keimer
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Abstract

The magnetic excitation spectrum of a YBa_2 Cu_3 O_7 crystal containing 0.5% of nonmagnetic (Zn) impurities has been determined by inelastic neutron scattering. Whereas in the pure system a sharp resonance peak at E ~ 40 meV is observed exclusively below the superconducting transition temperature T_c, the magnetic response in the Zn-substituted system is broadened significantly and vanishes at a temperature much higher than T_c. The energy-integrated spectral weight observed near q = (pi,pi) increases with Zn substitution, and only about half of the spectral weight is removed at T_c.

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H. F. Fong, P. Bourges, Y. Sidis, L. P. Regnault, J. Bossy, A. Ivanov, D. L. Milius, I. A. Aksay, B. Keimer. 1998-12-02. Effect of Nonmagnetic Impurities on the Magnetic Resonance Peak in YBa2Cu3O7. https://doi.org/10.1103/physrevlett.82.1939

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