Finite-element modeling of extraordinary magnetoresistance in thin film semiconductors with metallic inclusions

Using finite element analysis, the room temperature extraordinary magnetoresistance recently reported for a modified van der Pauw disk of InSb with a concentric embedded Au inhomogeneity has been calculated, using no adjustable parameters, as a function of the applied magnetic field and the size/geometry of the inhomogeneity. The finite element results are nearly identical to exact analytic results and are in excellent agreement with the corresponding experimental measurements. Moreover, several important properties of the composite InSb/Au system such as the field dependence of the current flow and of the potential on the disk periphery have been deduced, It is found that both the EMR and output voltage depend sensitively on the placement and size of the current and voltage ports.