Study on the resistivity and Hall effect of MgB2 and Mg0.93Li0.07B2

The temperature dependences of resistivity and Hall coefficient of MgB2 and Mg0.93Li0.07B2 were measured, and the temperature dependence of cot Theta (H) was calculated. The result of resistivity indicates that MgB2 and Mg0.9 3Li0.07B2 nearly have the same transition temperature. The possible effect on transition temperature has been discussed. The measurement of Hall coeff icient suggests the type of charge carriers is hole, and the Hall coefficie nt of Mg0.93Li0.07B2 becomes a little smaller compared with that of MgB2 wh ich is attributed to Li doping. Both the decrease with increasing temperatu re and the temperature dependence of cotangent of Hall angle are proportion al to the square of temperature.