Original scientific paper
Suppression of superconducting fluctuations in the electrical conductivity in oxygen underdoped and oxygen overdoped Bi2Sr2CaCu2O8 single crystals
László Forró
; École Polytechnique Fédérale de Lausanne,CH-1015 Lausanne, Switzerland
Abstract
The ab plane resistivity of the same single crystals of Bi2Sr2CaCu2O8 at different oxygen stoichiometries has been measured. As the oxygen content is lowered, the crystals become underdoped and the transition temperature (Tc) falls off from 85 to 58 K. Increasing the oxygen concentration causes the crystals to become overdoped and the Tc falls off again. The contribution to the electrical conductivity from superconducting fluctuations above Tc falls off drastically as oxygen concentration deviates from the optimum. We argue that the data may be consistent with a relatively large Maki - Thompson contribution, which falls off sharply both in the underdoped and overdoped regions - probably because of pair breaking.
Keywords
superconductivity; Bi2Sr2CaCu2O8; oxygen underdoped and overdoped; transition temperature; Maki - Thompson model; pair breaking
Hrčak ID:
301019
URI
Publication date:
3.10.1999.
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