Samples of Ag<sub>8</sub>Ge<sub>1-x</sub>Mn<sub>x</sub>Te<sub>6</sub> solid solutions with different manganese content (x = 0, 0.05, 0.1, 0.2) were prepared by fusing an...Samples of Ag<sub>8</sub>Ge<sub>1-x</sub>Mn<sub>x</sub>Te<sub>6</sub> solid solutions with different manganese content (x = 0, 0.05, 0.1, 0.2) were prepared by fusing and further pressing their powders under the pressure of 0.6 GPa. In addition of Mn atoms to the Ag<sub>8</sub>GeTe<sub>6</sub> compound leads to compression of their lattice. All p-type samples acquire a high resistance below the transition at temperatures of 180 - 220 K. The electrical conductivity of all compositions in the range of 220 - 300 K increases due to hopping mechanism, and at temperatures T > 320 K, a semiconductor characteristic is observed. By studying impedance spectra of samples, it was established that at 80 K solid solutions behave like a homogeneous dielectric material. At high temperatures and frequencies of an external electric field, a significant role of grain boundaries in conductivity was revealed. The dielectric anomaly occurring at low frequencies is also associated with an effect that manifests itself in the grain boundary.展开更多
文摘Samples of Ag<sub>8</sub>Ge<sub>1-x</sub>Mn<sub>x</sub>Te<sub>6</sub> solid solutions with different manganese content (x = 0, 0.05, 0.1, 0.2) were prepared by fusing and further pressing their powders under the pressure of 0.6 GPa. In addition of Mn atoms to the Ag<sub>8</sub>GeTe<sub>6</sub> compound leads to compression of their lattice. All p-type samples acquire a high resistance below the transition at temperatures of 180 - 220 K. The electrical conductivity of all compositions in the range of 220 - 300 K increases due to hopping mechanism, and at temperatures T > 320 K, a semiconductor characteristic is observed. By studying impedance spectra of samples, it was established that at 80 K solid solutions behave like a homogeneous dielectric material. At high temperatures and frequencies of an external electric field, a significant role of grain boundaries in conductivity was revealed. The dielectric anomaly occurring at low frequencies is also associated with an effect that manifests itself in the grain boundary.