Superconductivity and specific heat of Ru1-xTaxSr2GdCu2O8 and RuSr2Gd1.4Ce0.6Cu2Oy

Authors
Chen, XH Sun, Z Wang, KQ Xiong, YM Yang, HS Wen, HH Ni, YM Zhao, ZX
Citation
Xh. Chen et al., Superconductivity and specific heat of Ru1-xTaxSr2GdCu2O8 and RuSr2Gd1.4Ce0.6Cu2Oy, J PHYS-COND, 12(50), 2000, pp. 10561-10569
Citations number
15
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
JOURNAL OF PHYSICS-CONDENSED MATTER
ISSN journal
09538984 → ACNP
Volume
12
Issue
50
Year of publication
2000
Pages
10561 - 10569
Database
ISI
SICI code
0953-8984(200012)12:50<10561:SASHOR>2.0.ZU;2-G
Abstract
Samples of the compounds Ru1-xTaxSr2GdCu2O8 (Ru-1212) (n = 0.0, 0.05, 0.15) and RuSr2Gd1.4Ce0.6Cu2Oy (Ru-1222) have been characterized by means of the resistivity, thermoelectric power, magnetic susceptibility and specific he at. Ta doping apparently suppresses superconductivity for the Ru1-xTaxSr2Gd Cu2Oy system. The transport measurements show that the samples of Ru-1212 a re typical underdoped cuprates; the sample of Ru-1222 is nearly at the opti mal doping level. Specific heat measurements show an anomalous peak around T-c, indicating bulk superconductivity, whilst magnetic measurements seem t o show the absence of a bulk Meissner state, which results because the susc eptibility from the impurity Sr2GdRuO6 counters the diamagnetization from t he bulk superconductivity.