Quantum impurities and the neutron resonance peak in YBa2Cu3O7: Ni versus Zn

Authors
Sidis, Y Bourges, P Fong, HF Keimer, B Regnault, LP Bossy, J Ivanov, A Hennion, B Gautier-Picard, P Collin, G Millius, DL Aksay, IA
Citation
Y. Sidis et al., Quantum impurities and the neutron resonance peak in YBa2Cu3O7: Ni versus Zn, PHYS REV L, 84(25), 2000, pp. 5900-5903
Citations number
23
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW LETTERS
ISSN journal
00319007 → ACNP
Volume
84
Issue
25
Year of publication
2000
Pages
5900 - 5903
Database
ISI
SICI code
0031-9007(20000619)84:25<5900:QIATNR>2.0.ZU;2-W
Abstract
The influence of magnetic (S = 1) and nonmagnetic (S = 0) impurities on the spin dynamics of an optimally doped high temperature superconductor is com pared in YBa2(Cu0.97Ni0.03)(3)O-7 (T-e = 80 K) and YBa2(Cu0.99Zn0.01)(3)O-7 (T-c = 78 K). In the Ni-substituted system, the magnetic resonance peak (w hich is observed at E-r similar or equal to 40 meV in the purl system) shif ts to lower energy with a preserved E-r/T-e ratio while the shift is much s maller upon Zn substitution. By contrast Zn, but not Ni, restores significa nt spin fluctuations around 40 meV in the normal state. These observations are discussed in the light of models proposed for the magnetic resonance pe ak.