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Glass component induced hysteresis/memory effect in magnetoresistance of ferromagnetic Pr0.9Sr0.1CoO2.99

V. P. S. Awana·J. Nakamura·M. Karppinen·H. Yamauchi·S. K. Malik
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Abstract

Pr0.9Sr0.1CoO2.99 sample exhibits magnetoresistivity (MR) of up to 40 % at 5 K with a strong hysteresis/memory effect. Magnetisation measurements on Pr0.9Sr0.1CoO2.99 in an applied field of 100 Oe show that, as temperature decreases, the zero-field-cooled (ZFC) and field-cooled (FC) magnetisation curves branch clearly at 50 K, and a cusp appears in the ZFC branch at Tcusp 20 K. Magnetisation measurements in various fields between 100 and 10,000 Oe show that both the ZFC-FC branching temperature and, Tcusp, decrease with increasing field. The magnetization-field isotherms at 5 and 10 K show hysteresis loops typical of ferromagnets. No appreciable MR is seen in this compound at 50 K, i.e. at a temperature close to ZFC-FC branching temperature. At 20 K, negative MR of above 16% is observed without any hysteresis effect. We believe that the appearance of a ferromagnetic component at 5 K and 10 K (i.e. at temperatures below Tcusp) within the spin glass state of Co spins is responsible for both large MR and the prominent hysteresis/memory effect in MR.

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V. P. S. Awana, J. Nakamura, M. Karppinen, H. Yamauchi, S. K. Malik. 2002-10-17. Glass component induced hysteresis/memory effect in magnetoresistance of ferromagnetic Pr0.9Sr0.1CoO2.99. https://doi.org/10.1016/s0304-8853(02)00382-7

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