Thermoelectricity in correlated narrow-gap semiconductors.

摘要: We review many-body effects, their microscopic origin, as well impact onto thermoelectricity in correlated narrow-gap semiconductors. Members of this class---such FeSi and FeSb$_2$---display an unusual temperature dependence various observables: insulating with large thermopowers at low temperatures, they turn bad metals temperatures much smaller than the size gaps. This insulator-to-metal crossover is accompanied by spectral weight-transfers over energies optical conductivity a gradual transition from activated to Curie-Weiss-like behaviour magnetic susceptibility. show retrospective understanding these phenomena, discuss relation heavy-fermion Kondo insulators---such Ce$_3$Bi$_4$Pt$_3$ for which we present new results---and propose general classification paramagnetic insulators. From latter emerges orbital-selective insulator. Focussing on intermetallics such silicides, antimonides, skutterudites, Heusler compounds showcase successes challenges realistic simulation transport properties presence electronic correlations. Further, advert avenues correlations may contribute improvement thermoelectric performance.