Multifold enhancement of the thermoelectric figure of merit in p-type BaBiTe₃ by pressure tuning

As in the combinatorial approach to materials discovery, pressure tuning allows the phase space of interaction parameters that determine materials' properties to be explored more rapidly than by traditional means. Both the thermoelectric power and electrical conductivity of BaBiTe₃ are found to increase upon compression. As a result there is a dramatic increase in the dimensionless thermoelectric figure of merit ZT from ∼0.1 to ∼0.8. We suggest a mechanism for the enhancement involving an electronic topological transition. Such transitions can be induced both by means of pressure tuning and alloying, offering a potential route to reproducing the pressure induced improved behavior reported here by chemical means.