Determination of the electron characteristics of niobium nitride by an optical method

The dispersion of the complex dielectric constant epsilon(ω) epsilon1(ω)-iepsilon2(ω) of nibium nitride is measured in the 0.15 to 3.1 eV spectral range at temperatures 295 and 600 K. It is found that in the range indicated the optical properties of NbN are determined by the conductivity electrons and 5 interband transition bands to two of which little gaps of 0.13 and 0.27 eV correspond. The parameters of the conductivity electron band and interband transition bands and also their temperature dependences are determined. The following is obtained for the conductivity electrons; square of plasma frequency ωsub(pe)sup(2)=0.29 eV2, conductivity electron concentration Nsub(e) approximately 2x1020 cm-3, inverse relaxation time νsub(e)=0.325 eV. The energy gaps, plasma frequencies and inverse relaXation times are determined for the interband transition bands