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Dimensionally sharp inequalities for the linear entropy

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 نشر من قبل Simon Morelli
 تاريخ النشر 2019
  مجال البحث فيزياء
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We derive an inequality for the linear entropy, that gives sharp bounds for all finite dimensional systems. The derivation is based on generalised Bloch decompositions and provides a strict improvement for the possible distribution of purities for all finite dimensional quantum states. It thus extends the widely used concept of entropy inequalities from the asymptotic to the finite regime, and should also find applications in entanglement detection and efficient experimental characterisations of quantum states.



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