Carrier concentration dependence of electronic and magnetic properties of Sn-doped GaMnAs

Magnetotransport and magnetic properties of p-type GaMnAs layers, in which hole concentrations and Mn concentrations are independently controlled by Sn-donor incorporation, have been studied. Negative magnetoresistance has been enhanced by increasing Sn-incorporation. Hole concentration dependence of ferromagnetic transition temperature, determined from residual magnetization-temperature characteristic measured by DC-SQUID magnetometer has been investigated.