Anisotropic optical properties of YBa2Cu3O7

Abstract

Based upon the published results of YBa2Cu3O7 single-crystal reflectance spectra measured at room temperature, the empirical anisotropic spectral density functions and quasidielectric functions ε1j+iε2j [j=a,b,c] are determined in the 0.05 to 6 eV spectral range. These functions are an excellent fit to the reflectance spectra of samples in single-crystal, twin-crystal, and polycrystalline forms; they agree well with the published anisotropic transport and ellipsometry data. For polarizations along the a and b axes, the numerically determined empirical spectral density functions have shown two interband absorption peaks at 2.5 and 5 eV. For energy above 3 eV, the spectral density functions do not agree with the published theoretical interband conductivities that are derived from the band structure calculations.