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Quantum Geometric Tensor in $mathcal{PT}$-Symmetric Quantum Mechanics

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 نشر من قبل Jiangbin Gong Prof.
 تاريخ النشر 2018
  مجال البحث فيزياء
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A series of geometric concepts are formulated for $mathcal{PT}$-symmetric quantum mechanics and they are further unified into one entity, i.e., an extended quantum geometric tensor (QGT). The imaginary part of the extended QGT gives a Berry curvature whereas the real part induces a metric tensor on systems parameter manifold. This results in a unified conceptual framework to understand and explore physical properties of $mathcal{PT}$-symmetric systems from a geometric perspective. To illustrate the usefulness of the extended QGT, we show how its real part, i.e., the metric tensor, can be exploited as a tool to detect quantum phase transitions as well as spontaneous $mathcal{PT}$-symmetry breaking in $mathcal{PT}$-symmetric systems.



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