Temperature dependence of galvanomagnetic properties for Er-doped and undoped n-type InSe

The magnetoresistance and the Hall-effect measurements in undoped n-InSe (InSe) and Er-doped InSe (InSe:Er) samples in the temperature range 10-340 K were carried out. The InSe sample and the InSe:Er sample exhibit a null transverse magnetoresistance effect for T>160 and T>140 K, respectively, and a zero longitudinal magnetoresistance effect for T>160 and T>100 K, respectively. As the temperature increases, the carrier concentration obtained from the Hall-effect measurements in the InSe sample increases up to 40 K, decreases in the range 40-100 K, and increases for T>100 K, although the carrier concentration in the InSe:Er sample increases up to 300 K. In the same samples, the Hall mobility of the InSe sample increases up to 80 K and obeys to mu(H)(proportional to)T(-1.86) for T>80 K, although the Hall mobility of the InSe:Er sample decreases up to 340 K and obeys to mu(H)(proportional to) T--1.51 for T>80 K. The electrical conductivity, which is proportional to a product of the Hall mobility and the carrier concentration, of the InSe sample decreases with temperature for T>60 and T>100 K, respectively. (C) 1996 American Institute of Physics.