Logarithmic-to-nonlogarithmic flux-creep transition and magnetic-flux hardening in Bi-Sr-Ca-Cu-O superconducting ceramics

H. Safar; C. Durán; J. Guimpel; L. Civale; J. Luzuriaga; E. Rodriguez; F. de la Cruz; C. Fainstein; L. F. Schneemeyer; J. V. Waszczak

doi:10.1103/PhysRevB.40.7380

Logarithmic-to-nonlogarithmic flux-creep transition and magnetic-flux hardening in Bi-Sr-Ca-Cu-O superconducting ceramics

H. Safar, C. Durán, J. Guimpel, L. Civale, J. Luzuriaga, E. Rodriguez, F. de la Cruz, C. Fainstein, L. F. Schneemeyer, J. V. Waszczak

DOI 10.1103/PhysRevB.40.7380 · Physical Review B

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Abstract

A sharp temperature- and field-dependent transition from a logarithmic to a nonlogarithmic flux-creep behavior has been found in Bi-Sr-Ca-Cu-O superconductors. The transition is not followed by any noticeable change in the magnetization. However, vibrating-reed measurements show that it coincides with a strong hardening of the magnetic structure. The transition occurs at fields and temperatures well below the reversibility line. The possible relation to the recently proposed flux lattice melting is discussed.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
Bi4Ca2Sr4Cu4O16+y Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	85	Pressure not reported	onset
Bi4Ca2Sr4Cu4O16+y Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	65	Pressure not reported	zero_resistance
Bi4Ca2Sr4Cu4O16+y Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	81	Pressure not reported	midpoint