  We describe here a novel approach to the subject of thermoelectric devices.
The current best thermoelectrics are based on heavily doped semiconductors or
semimetal alloys. We show that utilization of electric field effect or
ferroelectric field effect, not only provides a new route to this problem,
bypassing the drawbacks of conventional doping, but also offers significantly
improved thermoelectric characteristics. We present here model calculation of
the thermoelectric figure of merit in thin films of Bi and PbTe, and also
discuss several realistic device designs.
