  Thermoelectric properties of a nanocontact made of two capped single wall
nanotubes (SWNT) are calculated within the tight-binding approximation and
Green's function method. It is found that semiconducting nanotubes can have
high Seebeck coefficient very near the actual Fermi energy. This in turn leads
to very high figures of merit easily exceeding one. Modifying the properties by
shifting the chemical potential can be achieved by doping or application of a
(nano-)gate voltage. The presence of impurities near the contact also strongly
modify the properties and this can be taken advantage of, in order to design
devices with high thermopower and figures of merit.
