Fe content variation and superconducting order parameter dimensionality in ErBa₂Cu_3-xFe_xO_7-_{<img src='/image/spc_char/delta1.gif' border=0>}

Abstract

The effects of predominantly chain-site dopant, Fe, concen­tration variation on superconducting order parameter fluctuations(SCOPF) in ErBa₂Cu_3-xFe_xO_7-_{<img src='/image/spc_char/delta1.gif' border=0>} polycrystalline bulk samples are presented and compared. A large reduction in OPD near the dynamic critical region is seen, suggesting an anomalous crossover and indicating a much slower suppression of superconductivity. Near to T_c the SCOPF behaviour suggests Cu-O network cou­pling deterioration. It is also observed that the SCOPF are invariant to Fe low concentrations and with Fe concentration increase these show marked dimensionality variation and increased oxygen content dependence. Higher Fe concentration is seen to promote a dimensionality reversal.