Influence of Sn on Galvanomagnetic Properties of Layered p‐(Bi1—xSbx)2Te3 Semiconductors

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 1-x Sb x ) 2 Te 3 (0 ≤ x ≤ 1.0) single crystals. Doping of (Bi 1-x 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 1-x Sb x ) 2 Te 3 . The quantization of the Hall resistivity Q H in the form of plateaus in the dependence of Q H on the magnetic field B is observed. The minima of the transverse magnetoresistivity Q correspond to the start of plateaus. The oscillation of Q 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 1-x Sb x ) 2 Te 3 serves as the reservoir. The valence band structure of (Bi 1-x Sb x ) 2 Te 3 is also discussed.