Thermoelectric figure of merit of Bi/Pb1-xEuxTe superlattices

An enhanced thermoelectric figure of merit Z(3D)T is predicted for Bi/(111) Pb1-xEuxTe superlattices. The values of Z(3D)T obtained for x approximate t o1 superlattices are 2.31, 1.55, and 1.61 at 300, 150, and 77 K, respective ly, showing that they are promising candidates for thermoelectric elements in the temperature range 77-300 K. Even with x as small as 0.1, where the c onduction-band offset DeltaE(c) is estimated to be 0.25 eV, the predicted Z (3D)T values are 1.75, 1.16, and 1.18 at 300, 150, and 77 K, respectively. It is proposed that other families of Bi-based superlattices, such as Bi/(1 11)CdTe superlattices, should also be good candidates for low-temperature t hermoelectric elements.