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On Local Unitary Equivalence of Two and Three-qubit States

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 نشر من قبل Shao-Ming Fei
 تاريخ النشر 2017
  مجال البحث فيزياء
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We study the local unitary equivalence for two and three-qubit mixed states by investigating the invariants under local unitary transformations. For two-qubit system, we prove that the determination of the local unitary equivalence of 2-qubits states only needs 14 or less invariants for arbitrary two-qubit states. Using the same method, we construct invariants for three-qubit mixed states. We prove that these invariants are sufficient to guarantee the LU equivalence of certain kind of three-qubit states. Also, we make a comparison with earlier works.


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