A µSR study of the magnetoresistive ruthenocuprates RuSr2Nd(1.8-x)Y0.2Ce(x)Cu2O(10-δ) (x = 0.95 and 0.80).
J Phys Condens Matter
; 23(36): 365704, 2011 Sep 14.
Article
de En
| MEDLINE
| ID: mdl-21865639
ABSTRACT
Zero field muon spin relaxation (ZF-µSR) has been used to study the magnetic properties of the underdoped giant magnetoresistive ruthenocuprates RuSr(2)Nd(1.8-x)Y (0.2)Ce(x)Cu(2)O(10-δ) (x = 0.95, 0.80). The magnetoresistance (MR) is defined so that MR = ((ρ(H)-ρ(0))/ρ(0)) and the giant magnetoresistive ruthenocuprates RuSr(2)Nd(1.8-x)Y(0.2)Ce(x)Cu(2)O(10-δ) exhibit a large reduction in electronic resistivity upon application of a magnetic field. The ZF-µSR results show a gradual loss of initial asymmetry A(0) at the ruthenium spin transition temperature, T(Ru). At the same time the electronic relaxation rate, λ, shows a gradual increase with decreasing temperature below T(Ru). These results have been interpreted as evidence for Cu spin cluster formation below T(Ru). These magnetically ordered clusters grow as the temperature is decreased thus causing the initial asymmetry to decrease slowly. Giant magnetoresistance is observed over a wide temperature range in the materials studied and the magnitude increases as the temperature is reduced from T(Ru) to 4 K which suggests a relation between Cu spin cluster size and |-MR|.
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Langue:
En
Journal:
J Phys Condens Matter
Sujet du journal:
BIOFISICA
Année:
2011
Type de document:
Article
Pays d'affiliation:
Royaume-Uni