Low-temperature metallic conductivity in the semiconductor TlSe having a chain structure

The results of experimental investigations of the electrical conductivity, magnetoresistance and Hall effect in the semiconductor TlSe with a chain structure are presented. The measurements of electrical conductivity have been carried out in two directions, i.e. parallel and perpendicular to the crystal c axis (the chain orientation). Galvanomagnetic measurements were made in magnetic fields of up to 60 kOe at different orientations of the magnetic and electric fields. The impurity conductivity is metallic in character with a negative magnetoresistance at low temperatures. The authors show that the low-temperature data can be explained by the model considering TlSe as a disordered system with a low-dimensional conductivity near the percolation limit.