The temperature dependence of the resistivity and the Hall effect in the range 0.3-300 K, and the Shubnikov-de Haas effect have been investigated in Sn-doped p-(Bi 1Àx Sb x ) 2 Te 3 ð0 x 1:0Þ single crystals. Doping of (Bi 1Àx Sb x ) 2 Te 3 with tin showed that Sn exhibits acceptor properties in all crystals. The anomalous temperature and magnetic field behavior of the Hall coefficient was explained quantitatively by a model, which involves the complicated two-valence band structure of p-(Bi 1Àx Sb x ) 2 Te 3 . The quantization of the Hall resistivity r H in the form of plateaus in the dependence of r H on the magnetic field B is observed. The minima of the transverse magnetoresistivity r correspond to the start of plateaus. The oscillation of r H is due to the presence of a carrier reservoir. An impurity resonant band with a high density of states in Sb 2 Te 3 or the second lower valence band with a higher hole effective mass in (Bi 1Àx Sb x ) 2 Te 3 serves as the reservoir. The valence band structure of (Bi 1Àx Sb x ) 2 Te 3 is also discussed.

The Hall effect and the Shubnikov-de Haas (SdH) effect have been investigated in magnetic fields up to 54 T in p-(Bi 1−x Sb x ) 2 Te 3 (0 x 1.0) Sn doped single crystals. Doping of (Bi 1−x Sb x ) 2 Te 3 with tin has shown that Sn exhibits acceptor properties in all crystals. We discuss the valence band structure of (Bi 1−x Sb x ) 2 Te 3 with the upper valence band (light hole band (LHB)), the lower valence band (heavy hole band (HHB)) and Sn-induced impurity band (IB). The Hall resistivity ρ H as a function of magnetic field shows quantization in the form of plateaus. The calculated Landau levels of the LHB with the best-fit parameters are in agreement with the experiment. The oscillation of ρ H is due to the presence of the carrier reservoir. The impurity resonant band with a high density of states or the HHB with a higher hole effective mass serve as the reservoir.

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