The Hall effect in a-GdxSi1−x at the metal–insulator transition

We have measured the Hall effect in 3-d amorphous GdxSi1−x films in the critical regime of the metal–insulator transition (MIT) at View the MathML source. a-GdxSi1−x exhibits a large negative magnetoresistance which is independent of the orientation of the magnetic field H with respect to the film and allows an in situ tuning of the conductivity through the MIT with H. We find an electron-like Hall coefficient RH. As the material becomes less metallic, RH increases. We find that RH is a critical quantity with critical exponent View the MathML source.