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Tenfold Magnetoconductance in a Non-Magnetic Metal Film

V. Yu. Butko·J. F. DiTusa·P. W. Adams
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Abstract

We present magnetoconductance (MC) measurements of homogeneously disordered Be films whose zero field sheet conductance (G) is described by the Efros-Shklovskii hopping law $G(T)=(2e^2/h)\exp{-(T_o/T)^{1/2}}$. The low field MC of the films is negative with G decreasing 200% below 1 T. In contrast the MC above 1 T is strongly positive. At 8 T, G increases 1000% in perpendicular field and 500% in parallel field. In the simpler parallel case, we observe {\em field enhanced} variable range hopping characterized by an attenuation of $T_o$ via the Zeeman interaction.

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V. Yu. Butko, J. F. DiTusa, P. W. Adams. 2000-03-14. Tenfold Magnetoconductance in a Non-Magnetic Metal Film. https://doi.org/10.1103/physrevlett.85.162

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