Effect of Sr-for-Ba isovalent substitution on the local structure, hole distribution and magnetic irreversibility of Cu(Ba,Sr)2YbCu2O6.95(2)

Abstract

The effect of Sr II -for-Ba II isovalent substitution on the magnetic irreversibility field (H irr ) of However, from neutron diffraction data analysis it is found that Sr substitution breaks the conductive CuO chains in BB by shifting part of the excess oxygen atoms from the characteristic b-axis lattice site to the a-axis site. This is believed to decrease the concentration of mobile holes in the BB, as supported by the results of TEP measurements. The lower H irr (T) lines of the Srsubstituted samples may thus be attributed to the lower concentration of mobile holes in BB.