Giant thermopower and figure of merit of semiconducting polaronic nanolayers
journal contributionposted on 24.08.2010 by A.S. Alexandrov, A.M. Bratkovsky
Any type of content formally published in an academic journal, usually following a peer-review process.
Polarons—electrons coupled with lattice vibrations—play a key role in transport and optical properties of many semiconductors. Here, we calculate the energy spectrum and thermopower of Fröhlich polarons confined to a potential well as a function of the well thickness. We show that the polaron mass enhancement in 2+ϵ dimensions explains a giant thermoelectric power recently observed in doped semiconducting nanolayers (multiple quantum wells) and propose a route for enhancing the performance of thermoelectric energy nanoconverters by increasing their figure of merit by more than one order of magnitude.