A possible correlation between suppression of superconductivity, magnetic ordering and normal state resistivity parameters in the Yb1−xprxba2cu3o7−_ system

Abstract

Polycrystalline samples of the Pr doped Yb1−xPrxBa2Cu3O7− (i.e. Yb(Pr)-123) system for 0 x 1 have been investigated for resistivity and magnetization M as a function of temperature in normal and superconducting states. The gradual decrease in superconducting critical temperature Tc(x) is found to be correlated with the xdependent ratio of resistivity slope (d =dT )cc (corresponding to the linear (T) region) and residual resistivity 0. In particular, the observed di erence of critical Pr concentration where superconductivity is destroyed (xc) in Yb(Pr)-123 (xc 0:65) and Y(Pr)-123 (xc 0:55) matches with the di erence in the value of Pr concentration where the ratio (d =dT )cc= 0 tends to go to zero in them. The M(T) data of the Yb(Pr)-123 samples show magnetic ordering for x > xc at characteristic temperatures, Tn, that increase with x. Interestingly, the Yb(Pr)-123 sample with Pr content (x = 0:6) near xc reveals several anomalous features like transition from metallic to semiconducting-like (T), an excessive broadening of the diamagnetic transition and weakening of the M(T) signal related to antiferromagnetic ordering of Pr ions. These observations can be consistently interpreted by assuming the presence of dynamically fluctuating striped phase in these systems.