Pressure-dependent thermopower of individual Bi nanowires

Abstract

The 240–620nm diameter nanowires were freely suspended and thermopower measurements were carried out over the temperature range 4–300K and for stresses as high as 1GPa. The peaks of up to 80μV∕K that are observed around 40K are interpreted in terms of a model of diffusion thermopower under strong electron and hole-boundary scattering. The partial Seebeck coefficients are calculated from the stress-dependent carrier Fermi energies obtained from magnetoresistance measurements. The prospect of Bi nanowire arrays achieving high thermoelectric figure of merit is discussed.