Effect of elastic stress on the resistivity and Tc of (Bi, Pb) 2Sr 2Ca n−1 Cu nO x

Abstract

We have measured the effect of elastic uniaxial stress σ in the a direction on the superconducting transition temperature T c of (Bi, Pb) 2Sr 2Ca 1Cu 2O χ (2212) and (Bi, Pb) 2Sr 2Ca 2Cu 3O χ (2223). We find dT/ dσ 11=-10±2 K/GPa for 2212 and -6±2K/ GPa for the 2223 compound. Combining these results with those of others on d T c/d P we find that dT c / dσ 33=+ 18 K/GPa. An estimate of the elastic constants of these compounds from the work of others together with these results implies that the change in T c with a fractional change in the c-axis spacing is probably positive, although the uncertainties in the elastic constants make this estimate subject to a large uncertainty. The resistance changes by less than 1 part in 12 000 for strains up to 0.5%, implying that dln ϱ/ dσ 11=-76 x10 -3 GPa -1