Optical anisotropy in the Pb2Sr2(Y, Ca)Cu3O8+δ superconductor

✍ Scribed by J. Kircher; M. Cardona; M. Garriga; B. Nick; M. Dürrler; A. Zibold; H.P. Geserich

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 643 KB
• Volume: 174
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(91)91573-m

✦ Synopsis

We present ellipsometric and reflectance measurements of the polarization dependence of the optical response of PbzSrz(Y, Ca)CusOs+a for light polarized parallel and perpendicular to the CuZO planes on a single crystal. A plasma edge can only be observed in the a-direction, indicating a carrier concentration of 0.28 holes per unit cell which is comparable to the carrier con-. . centration m YBalCuaOb.s. In the region between 1.7 and 5 eV several strucaures are present in the optical spectra and can be analyzed in terms of a band structure calculation by Mattheiss et al. Most noteworthy in this energy region is the absence of a sharp excitation at 4.1 eV suggesting that the Ba-admixture to the final state is nmportant for the appearance of this transition in Y Ba2Cuj06.