Optical Reflectivity Studies of Polycrystalline La4BaCu5O13 and La2SrCu2O6+Sigma

摘要

Optical reflectivity measurements have been made on polycrystalline samples of La4BaCu5O13 and La2SrCu2O6+delta, two nonsuperconducting oxides. The effective optical conductivities of these materials show a peak between 0.5 and 1 eV, similar in magnitude to that previously observed in YBa2Cu3O7-x and La2-xSrxCuO4. Our observations indicate that this spectral feature is an extrinsic effect related to the composite nature of the samples and is not relevant to superconductivity in this class of materials. Keywords: Reprints, Lanthanum compounds, Strontium compounds, Copper oxides, Barium compounds. (MJM)