Spin Glass Behavior of New Perovskites Ba2In2−xCoxO5 (0.5 ⩽x⩽1.70)

✍ Scribed by A.D. Lozano Gorrı́n; P. Núñez; M.A. López de la Torre; J. Romero de Paz; R. Sáez Puche

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 255 KB
• Volume: 165
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2002.9515

✦ Synopsis

New oxides of general formula Ba 2 In 2Àx Co x O 5 (0.5 x 1.70) have been synthesized as polycrystalline materials and fully characterized by means of X-rays. They are all isostructural and crystallize in a perovskite-type structure, showing cubic symmetry, space group Pm3m. The magnetic properties of these oxides have been studied by v ac and v dc measurements as a function of magnetic field and temperature. In the case of x=0.5 (BaIn 1.50 Co 0.5 O 5 ) the sample remains paramagnetic from 200 to 2 K. However, the magnetic behavior of the oxides Ba 2 In 2Àx Co x O 5 (0.70 x 1.70) is rather different: v dc shows broad maxima which are shifted with the x cobalt content. Below this temperature a strong irreversibility between the zero-field-cooled (ZFC) and field-cooled (FC) curves has been detected, more pronounced as the cobalt content is higher. v ac measurements also show all the common features of spin glasses, fully confirmed from the analysis of the non linear part of the v dc .