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Anderson transitions in three-dimensional disordered systems with randomly varying magnetic flux

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 نشر من قبل Kawarabayashi Tohru
 تاريخ النشر 1998
  مجال البحث فيزياء
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The Anderson transition in three dimensions in a randomly varying magnetic flux is investigated in detail by means of the transfer matrix method with high accuracy. Both, systems with and without an additional random scalar potential are considered. We find a critical exponent of $ u=1.45pm0.09$ with random scalar potential. Without it, $ u$ is smaller but increases with the system size and extrapolates within the error bars to a value close to the above. The present results support the conventional classification of universality classes due to symmetry.

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The Anderson transitions in a random magnetic field in three dimensions are investigated numerically. The critical behavior near the transition point is analyzed in detail by means of the transfer matrix method with high accuracy for systems both wit h and without an additional random scalar potential. We find the critical exponent $ u$ for the localization length to be $1.45 pm 0.09$ with a strong random scalar potential. Without it, the exponent is smaller but increases with the system sizes and extrapolates to the above value within the error bars. These results support the conventional classification of universality classes due to symmetry. Fractal dimensionality of the wave function at the critical point is also estimated by the equation-of-motion method.
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