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Hall-conductivity sign change and fluctuations in amorphous Nb$_{x}$Ge$_{1-x}$ films

Nobuhito Kokubo·Jan Aarts·Peter H. Kes
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Abstract

The sign change in the Hall conductivity has been studied in thin amorphous Nb$_{1-x}$Ge$_x (x\approx$0.3) films. By changing the film thickness it is shown that the field at which the sign reversal occurs shifts to lower values (from above to below the mean-field transition field $H_{c2}$) with increasing film thickness. This effect can be understood in terms of a competition between a positive normal and a negative fluctuation contribution to the Hall conductivity.

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Nobuhito Kokubo, Jan Aarts, Peter H. Kes. 2001-03-08. Hall-conductivity sign change and fluctuations in amorphous Nb$_{x}$Ge$_{1-x}$ films. https://doi.org/10.1103/physrevb.64.014507

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