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تسجيل مستخدم جديدElectrical Noise From Phase Separation In Pr2/3Ca1/3MnO3 Single Crystal
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Low frequency electrical noise measurements have been used to probe the electronic state of the perovskite-type manganese oxide Pr2/3Ca1/3MnO3 versus temperature and in the vicinity of the field-induced transition from the insulating, charge-ordered state (I-CO) to the metallic, ferromagnetic state (M-F). At high temperature we have observed a high level of the excess noise with mainly a gaussian distribution of the resistance fluctuations, and the associated power spectral density has a standard 1/f dependence. However, in the hysteretic region, where the electrical resistance depends dramatically on the sample history, we have observed a huge non-gaussian noise characterized by two level fluctuator-like switching (TLS) in the time domain. We discuss the origin of the noise in terms of percolative behavior of the conductivity. We speculate that the dominant fluctuators are manganese clusters switching between the M-F and the I-CO phases.
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Giant Random Telegraph Noise (RTN) in the resistance fluctuation of a macroscopic film of perovskite-type manganese oxide La2/3Ca1/3MnO3 has been observed at various temperatures ranging from 4K to 170K, well below the Curie temperature (TC = 210K).
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