Abstract
The oxygen deficiency, δ, dependence of the second peak effect and the irreversibility field in the magnetization hysteresis curves was investigated on Sr-overdoped (La 1− x Sr x ) 2CuO 4−δ single crystals with various δ/ After reducing δ by annealing the crystals at various oxygen partial pressures, the critical temperature, T c , was systematically enhanced with decreasing δ. When the magnetic field was applied parallel to the c-axis, the second peak field, B 2pk, shifted towards higher fields with decreasing δ, while the irreversibility field, B irr, showed a slight δ dependence except in the most overdoped crystal. The results indicate that B 2pk and B irr depend on the different pinning mechanisms although both fields are well described by the same scaling law, B ∝ (1 − T T c ) n (n = 1.5−2) , in the whole temperature range from 4.2 K to T c.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
