Potential thermoelectric properties of PbTe/Pb1-xEuxTe quantum wells

Thermoelectric opportunities of PbTe/Pb_1-xEu_xTe quantum well structures are investigated theoretically. The electron energetic spectrum and the Fermi level position are calculated in dependence on the quantum well width and the potential barrier height for (111) and (100) oriented structures, taking into account the multivalley character of the bulk semiconductors. The electrical conductivity and Seebeck coefficient are determined for transport along the well layers using the variational method. The carrier scattering both on optical and acoustical phonons is taken into account. It is found that for (100)-structures the conductivity decreases and Seebeck coefficient increases with the well width decreasing while for (111)-structures the latter varies weakly. The values of the thermoelectric power factor are determined and analyzed. It is shown that the values of the power factor are higher in the (100) oriented structures