engleski

Phonon-enhanced thermoelectric power of Y-Al-Ni-Co decagonal approximnat

We have investigated anisotropic electrical resistivity and thermoelectric power of the ypsilon-phase Al–Ni–Co (Y–Al–Ni–Co) decagonal approximant with composition Al76Co22Ni2. The crystalline-direction-dependent measurements were performed along three orthogonal directions a*, b and c of the Y–Al–Ni–Co unit cell, where (a, c) monoclinic atomic planes are stacked along the perpendicular b direction. Anisotropic electrical resistivity is low in all crystalline directions, appearing in the order ρa* > ρc > ρb and showing positive temperature coefficient typical of electron-phonon scattering mechanism. Thermopower shows electron-phonon enhancement effect. Anisotropic bare thermopower (in the absence of electron-phonon interactions) was extracted, appearing in the same order as the resistivity, ΙSa*bare/TΙ > Ι Scbare/T Ι > Ι Sbbare/T Ι.

thermoelectric power; Y-Al-Ni-Co decagonal approximnat

nije evidentirano