Optical properties of PbTe doped with Nd

Single crystals of lead telluride doped with Nd were synthesized using the Bridgeman method. Room temperature far infrared reflectivity spectra were measured for PbTe samples with Nd content in the range 0.2–0.9 at.%. Optical reflectivity in the far infrared range was measured in the temperature range between 10 and 300 K for a highly polished PbTe sample with 0.6 at.% Nd. The experimental diagrams were numerically analyzed with a fitting procedure using a modified plasmon–phonon model. Two local modes were noted and their origin was discussed. Optical electron mobility was calculated for all analyzed samples.