Size-effects in the magnetoresistance of Al and in films

Experiments of Føsrsvoll and Holwech on size-effects in the magneto-resistance of thin Al and In films are interpreted with the aid of a two-band model. Using this model the size-affected resistivity in a magnetic field can be expressed in terms of the size-affected resistivity tensor elements of each band. A comparison between the experimental results on metals which show bulk magnetoresistance and theoretical results obtained from the simple free-electron theory then turns out satisfactorily.