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Negative magnetoresistance in the nearest-neighbour hopping conduction in granular gold film

B. I. Belevtsev·E. Yu. Beliayev·Yu. F. Komnik·E. Yu. Kopeichenko
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Abstract

The low temperature (0.5-55 K) conduction of semicontinuous gold film vacuum deposited at T \approx 50 K is studied. The film is near the percolation threshold (thickness 3.25 nm). Its resistance is extremely sensitive to the applied voltage U. At low enough U the film behaves as an insulator (two-dimensional granular metal). In this state the dependences R(T) \propto \exp (1/T) (for T \leq 20 K) and R(U) \propto \exp (1/U)) (for T \leq 1 K and U > 0.1 V) are observed. Magnetoresistance (MR) is negative and can be described by ΔR(H)/R(0) \propto -H^2/T. This negative MR which manifests itself for nearest-neighbour hopping is rather uncommon and, up to now, has not been clarified. The possible mechanisms of such case of negative MR are discussed.

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B. I. Belevtsev, E. Yu. Beliayev, Yu. F. Komnik, E. Yu. Kopeichenko. 1998-08-28. Negative magnetoresistance in the nearest-neighbour hopping conduction in granular gold film. https://doi.org/10.1016/s0921-4526(98)00445-1

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