Effect of copper doping on kinetic phenomena in n-Bi2Te2.85Se0.15

In single crystals of copper-doped and undoped Bi2Te2.85Se0.15 solid solutions with an electron concentration close to 1 x 1019 cm-3, the temperature dependences are investigated for the Hall (R123, R321) and Seebeck (S11) kinetic coefficients, the electrical-conductivity (σ11), Nernst-Ettingshausen (Q123), and thermal conductivity (k11) coefficients in the temperature range of 77-400 K. The absence of noticeable anomalies in the temperature dependences of the kinetic coefficients makes it possible to use the one-band model when analyzing the experimental results. Within the framework of the one-band model, the effective mass of density of states (md ∼ 0.8m0), the energy gap (εg ∼ 0.2 eV), and the effective scattering parameter (reff ∼ 0.2) are estimated. The obtained value of the parameter reff is indicative of the mixed electron-scattering mechanism with the dominant scattering by acoustic phonons. Data on the thermal conductivity and the lattice resistivity obtained by subtracting the electron contribution according to the Wiedemann-Franz law are presented