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Universal Finite-Size Scaling around Topological Quantum Phase Transitions

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 نشر من قبل Tobias Gulden
 تاريخ النشر 2015
  مجال البحث فيزياء
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The critical point of a topological phase transition is described by a conformal field theory, where finite-size corrections to energy are uniquely related to its central charge. We investigate the finite-size scaling away from criticality and find a scaling function, which discriminates between phases with different topological indexes. This function appears to be universal for all five Altland-Zirnbauer symmetry classes with non-trivial topology in one spatial dimension. We obtain an analytic form of the scaling function and compare it with numerical results.



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