Three-terminal semiconductor junction thermoelectric devices: improving performance

摘要

A three-terminal thermoelectric device based on a $p$-$i$-$n$ semiconductorjunction is proposed, where the intrinsic region is mounted onto a, typicallybosonic, thermal terminal. Remarkably, the figure of merit of the device isgoverned also by the energy distribution of the {\em bosons} participating inthe transport processes, in addition to the electronic one. An enhanced figureof merit can be obtained when the relevant distribution is narrow and theelectron-boson coupling is strong (such as for optical phonons). We study theconditions for which the figure of merit of the three-terminal junction can begreater than those of the usual thermoelectric devices made of the samematerial. A possible setup with a high figure of merit, based onBi$_2$Te$_3$/Si superlattices, is proposed.