6533b859fe1ef96bd12b7f49

RESEARCH PRODUCT

Optical conductivity inYBa2Cu3O7−δthin films

subject

description

The real and imaginary parts of the optical conductivity ${\ensuremath{\sigma}}_{1}+i{\ensuremath{\sigma}}_{2}$ of partly untwinned ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ thin films were measured by submillimeter spectroscopy for frequencies from 100 GHz to 1 THz. The frequency dependence of the conductivity below ${T}_{C}$ can be described by a narrow Drude-like peak with strongly temperature-dependent relaxation rates. ${\ensuremath{\sigma}}_{1}(\ensuremath{\nu})$ does not extrapolate to the universal d-wave value at 0 K. Impurity scattering significantly different to the unitary limit has to be assumed to achieve agreement with recent theoretical results. Including published infrared results we present ${\ensuremath{\sigma}}_{1}(\ensuremath{\nu})$ in the spectral range from 0.1--100 THz.