Low energy excitations in crystalline perovskite oxides: Evidence from noise experiments
نویسندگان
چکیده
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 ≈ 70-80 meV which produce peak in the noise at T ≈ 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. email: [email protected]. ernet.in On lien to National Physical Laboratory, New Delhi 110012, India.
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