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Giant 1/f noise in perovskite manganites: evidence of the percolation threshold

V. Podzorov·M. Uehara·M. E. Gershenson·T. Y. Koo·S-W. Cheong
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Abstract

We discovered an unprecedented magnitude of the 1/f noise near the Curie temperature Tc in low-Tc manganites. The scaling behavior of the 1/f noise and the resistance provides strong evidence of the percolation nature of the ferromagnetic transition in the polycrystalline samples. The step-like changes of the resistance with temperature, observed for single crystals, suggest that the size of the ferromagnetic domains depends on the size of crystallites.

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V. Podzorov, M. Uehara, M. E. Gershenson, T. Y. Koo, S-W. Cheong. 1999-10-14. Giant 1/f noise in perovskite manganites: evidence of the percolation threshold. https://doi.org/10.1103/physrevb.61.r3784

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