Hole superconductivity in the electron-doped superconductor Pr2-xCexCuO4

We measure the resistivity and Hall angle of the electron-doped superconductor Pr2-xCexCuO4 as a function of doping and temperature. The resistivity rho(xx) at temperatures 100 K < T < 300 K is mostly sensitive to the electrons. Its temperature behavior is doping independent over a wide doping range and even for nonsuperconducting samples. On the other hand, the transverse resistivity rho(xy), or the Hall angle theta(H), where cot(theta(H))=rho(xx)/rho(xy), is sensitive to both holes and electrons. Its temperature dependence is strongly influenced by doping, and cot(theta(H)) can be used to identify optimum doping (the maximum T-c) even well above the critical temperature. These results lead to a conclusion that in electron doped cuprates holes are responsible for the superconductivity.