Temperature dependence of electron concentration in intrinsic-like HgTe

Measurement of the Hall effect and the conductivity are performed on HgTe sample characterized by an electron mobility of 106 cm2/Vs at 1.6 K. The range of temperatures investigated is 1.6 to 32 K and the external magnetic field covers the region 50 to 800 G. The interpretation of the data based on the conductivity tensor components analysis shows that the sample contains 5 x 1016 cm-3 acceptors. The acceptor ionization energy is estimated to be 2 MeV. It is shown that a simple one-carrier expression for the Hall constant may give wrong results for the electron concentration, differing by a factor of two from the correct value. From the behaviour of conduction electron concentration below 6 K it is found that the conduction-valence band overlap is smaller than 0.3 MeV. (author)