Enhancing and protecting quantum correlations of a two-qubit entangled system via non-Hermitian operation

  • Yan-Yi Wang
  • Mao-Fa FangEmail author


We investigate the dynamics of geometric measure of quantum discord and negativity as a measure of quantum entanglement for the system under the local non-Hermitian operation. Numerical calculations demonstrate that quantum discord and entanglement as two kinds of typical measures of quantum correlations can exceed respective initial value, and their evolution behaviors appear to violate conventional properties which formulates quantum discord and quantum entanglement are invariants under local operations. Our results show that non-Hermitian operation achieves distinctive effects on enhancement and protection of quantum correlations, which is mostly aroused by the non-Hermiticity and the non-unitarity of the non-Hermitian operation.


Geometric measure of quantum discord Quantum entanglement Non-Hermitian dynamics 



This work is supported by the National Natural Science Foundation of China (Grant No. 11374096).


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Authors and Affiliations

  1. 1.Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, College of Physics and Information ScienceHunan Normal UniversityChangshaChina
  2. 2.Synergetic Innovation Center for Quantum Effects and Applications, College of Physics and Information ScienceHunan Normal UniversityChangshaChina

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