Formation and mobility of oxygen vacancies in RuSr2GdCu2O8

Article

关键词: ANELASTIC RELAXATION;    INTERNAL-FRICTION;    YBA2CU3O6+X;    DIFFUSION;    TRANSPORT;    RU;   

DOI  :  10.1103/PhysRevB.67.144519

来源: SCIE

【 摘 要 】

Oxygen vacancies are introduced in the RuO2 and possibly CuO2 planes of RuSr2GdCu2O8 by annealing in vacuum above 600 K. The diffusive jumps of the O vacancies are accompanied by a reorientation of the local distortion, and are probed by measuring the elastic energy loss and modulus versus temperature at 1-10 kHz. An intense acoustic absorption peak develops near 670 K at 1 kHz and finally stabilizes after heating up to 920 K in vacuum. The analysis of the peak shows a barrier for the O diffusion of similar or equal to1.4 eV, and a slowing down of Curie-Weiss type, with T-C=400-470 K, due to the interaction among the O vacancies. A secondary peak is attributed to O vacancies trapped at defects in the RuO2 planes, or to vacancies in the CuO2 planes. No sign of structural phase transformation is found up to 920 K.

【 授权许可】

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