The magnetoresistance (MR) of amorphous indium oxide films on the insulating side near the superconductor-insulator transition was measured. Variable range hopping is evident in the presence of a high enough magnetic field even in the temperature range where simple activation prevails in the absence of a magnetic field, which strongly suggests the existence of localized superconducting granules. Consequently, junction breaking between superconducting granules and pair breaking effects dominate the MR at low enough temperatures. As those effects caused by the local superconductivity on MR decrease rapidly with increasing temperature, an intrastate interaction effect becomes significant. The observed MR is fitted to a theoretical expression which includes junction breaking, pair breaking and intrastate interaction terms. The temperature dependence of the fitting parameters shows qualitative agreement with theoretical expectations.

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The magnetoresistance (MR) was measured in films of amorphous indium oxide at the region of weak-strong localization crossover (WSLC). The change from positive to negative MR was observed commonly in the samples as temperature increased, passing through 8-10 K, which falls within the WSLC region of each sample. The observed MR is fitted to a formula composed of the intrastate interaction and the delocalization (DL) terms. The fitting results show that the intrastate interaction term remains up to the high limit of the WSLC region, above which the weak localization is valid, while the DL effect is evident down to the low limit of the WSLC region, below which the strong localization prevails. Temperature dependences of the fitting parameters show qualitative agreement with theoretical expectations.

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