Abstract
We study the effects of Pb substitution in single crystals of the high-temperature superconductor ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{8+\ensuremath{\delta}}$. We compare Pb-substituted samples with ``pure'' (unsubstituted) crystals in terms of structure, cation composition, and the temperature dependences of ac susceptibility and Raman scattering. We find that ${\mathrm{Pb}}^{2+}$ primarily substitutes for ${\mathrm{Bi}}^{3+}$, leading directly to a ${T}_{c}$ reduction characteristic of overdoped samples. We also observe structural changes related to the superlattice modulation along $b$*. Raman scattering studies indicate that some Pb atoms go to Sr sites. Low-temperature electronic Raman scattering shows further evidence for cation overdoping by comparison with oxygen annealed pure ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{8+\ensuremath{\delta}}$.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.