Giant scattering parameter and enhanced thermoelectric properties originating from synergetic scattering of electrons in semiconductors with metal nanoinclusions

The scattering processes of electrons in semiconductors with metal nanoinclusions were theoretically investigated in the framework of relaxation time approximation, in which perturbation theory was used to calculate scattering probabilities analytically. Our results reveal that it is not the single scattering at interface potential barriers caused by the nanoinclusions but the synergetic scattering of electrons at ionized impurities and the interface potential barriers or wells that can produce giant scattering parameter lambda (=3.3-4.7). Due to giant lambda and enhanced thermopower, the estimated figure of merit ZT=3.4 at 800 K for PbTe with Pb nanoinclusions. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3515298]