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Low energy excitations in crystalline perovskite oxides: Evidence from noise experiments

Arindam Ghosh·A. K. Raychaudhuri·R. Sreekala·M. Rajeswari·T. Venkatesan
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Abstract

In this paper we report measurements of 1/f noise in a crystalline metallic oxide with perovskite structure down to 4.2K. The results show existence of localized excitations with average activation energy $\approx$ 70-80 meV which produce peak in the noise at T $\approx$ 35-40K. In addition, it shows clear evidence of tunnelling type two-level-systems (as in glasses) which show up in noise measurements below 30K.

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Arindam Ghosh, A. K. Raychaudhuri, R. Sreekala, M. Rajeswari, T. Venkatesan. 1998-11-28. Low energy excitations in crystalline perovskite oxides: Evidence from noise experiments. https://doi.org/10.1103/physrevb.58.r14665

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