DIELECTRIC-PROPERTIES OF YNI2B2C

The dielectric function of the quarternary superconductor YNi2B2C has been derived in an energy range from 10meV up to 50eV by linking toget her optical reflectance and electron energy loss measurements, obtaine d from polycrystalline samples at room temperature. The low energy par t Of the spectrum was additionally investigated in a temperature range from 10K up to 300K. In order to determine the anisotropy of this com pound, the reflectance spectra of a single crystal were taken, using p olarized light with polarization along the crystallographic axes. The single crystal data exhibit a normal Drude-like metallic behaviour, wh ile the polycrystalline data can only be interpreted by means of a str ong energy dependent scattering rate, which has been interpreted as re sulting from strong electron-phonon coupling.