Infrared spectra of bismuth family of superconductors Bi2Sr2Can-1CunO4+2n+y

摘要

FTIR spectra of bismuth family ofsuperconductors are studied. Polycrystalline samples of bismuthsuperconductors are prepared choosing an off-stoichiometriccomposition for phase stabilisation and reproducibility.Vibrational modes are strongly affected by the holes introducedinto the CuO planes. Mid IR spectra of the Bismuth system wasrecorded using Bruker IFS 66v and the high frequency oxygenvibrations of the system is discussed based on the factor groupanalysis for both symmorphic and non-symmorphic spacegroups 14/mmm, Fmmm and Amaa of different structures based onthe modulated superstructure.