Ana Akrap, Alberto Ubaldini, Enrico Giannini, Laszlo Forro
We report a detailed study of the temperature and composition dependence of the resistivity and thermopower for a series of bismuth chalcogenides Bi$_2$Te$_{3-x}$Se$_x$. The temperature dependence of the thermopower can be semi-quantitatively described by a simple model for an extrinsic semiconductor. We show that, by substituting selenium for tellurium, the Fermi level can be continuously tuned from the valence band into the conduction band. The maximum values of the thermopower, bulk band gap as well the activation energy are found for x~1.
View original:
http://arxiv.org/abs/1210.3901
No comments:
Post a Comment