High magnetic field study of HoBaCo2O5:5 and GdBaCo2O5:5 layered cobaltites: the effect of rare-earth size

C. FRONTERA; M. RESPAUD; J.L. GARCÍA MUÑOZ; A. CANEIRO; J.M. BROTO; A. LLOBET

PHYSICA B - CONDENSED MATTER

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2004 vol. 347 p. 246 - 249

0921-4526

By means of high-pulsed magnetic field up to m0H ¼ 32 T we have studied HoBaCo2O5þd ðd ¼ 0:52ð1ÞÞ: The highfieldMðHÞ integrated curves evidence a magnetic field-induced phase transition visible from about T ¼ 75 to 275 K:The obtained results are compared with the field-induced transition found for GdBaCo2O5þd (with d ¼ 0:54ð2Þ). Thejump of the magnetization at the field-induced transition is independent of the rare earth at this level of oxygen content.In contrast, we have observed larger values of the critical field, and that the transition persists up to higher temperature,when reducing the rare-earth size. This indicates that the low-temperature antiferromagnetic phase becomes more stablewhen the size of the rare earth is reduced.