CuNQR study of host and guest spin dynamics in impurity-doped YBa2Cu4O8

Citation
Y. Itoh et al., CuNQR study of host and guest spin dynamics in impurity-doped YBa2Cu4O8, PHYSICA C, 357, 2001, pp. 69-73
Citations number
20
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICA C
ISSN journal
0921-4534 → ACNP
Volume
357
Year of publication
2001
Part
1
Pages
69 - 73
Database
ISI
SICI code
0921-4534(200108)357:<69:CSOHAG>2.0.ZU;2-F
Abstract
We present the planar Cu-63 nuclear spin-lattice relaxation study of impuri ty-doped YBa2(Cu1-xMx)(4)O-8 (M = Ni, Zn) at T = 4.2-300 K with Cu nuclear quadrupole resonance (NQR) spin-echo technique. In the light of an impurity -induced NQR relaxation theory, we estimated the host Cu nuclear spin-latti ce relaxation time (T-l)HOST, the impurity-induced Cu nuclear spin-lattice relaxation time (tau (l)), and the wipeout region around the impurity in th e superconducting state. The pseudo spin-gap behavior of the host Cu antife rromagnetic spin fluctuation above T-c is not readily removed by a small am ount of the impurity. The Zn-induced non-Korringa behavior of (T-l)HOST bel ow T-c is in sharp contrast to the doping effect of the magnetic impurity N i. (C) 2001 Elsevier Science B.V. All rights reserved.