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Mesoscopic, Non-equilibrium Fluctuations of Inhomogeneous Electronic States in Manganites

V. Podzorov·C. H. Chen·M. E. Gershenson·S-W. Cheong
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Abstract

By using the dark-field real-space imaging technique of transmission electron microscopy (TEM), we have observed slow 200 A-scale fluctuations of charge-ordered (CO) phase in mixed-valent manganites under a strong electron beam irradiation. In addition to these unusual fluctuations of the CO phase, we observed the switching-type fluctuations of electrical resistivity in the same sample, which were found to be as large as several percents. Systematic analysis indicates that these two different types of fluctuations with a similar time scale of the order of seconds are interconnected through a meta-stable insulating charge-disordered state. Current dependence of the fluctuations suggests a non-equilibrium nature of this slow dynamics.

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V. Podzorov, C. H. Chen, M. E. Gershenson, S-W. Cheong. 2001-05-21. Mesoscopic, Non-equilibrium Fluctuations of Inhomogeneous Electronic States in Manganites. https://doi.org/10.1209/epl%2Fi2001-00429-5

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