Nonlinear Improvement of Qubit-qudit Entanglement Witnesses
- URL: http://arxiv.org/abs/2001.05269v1
- Date: Wed, 15 Jan 2020 12:29:55 GMT
- Title: Nonlinear Improvement of Qubit-qudit Entanglement Witnesses
- Authors: Shu-Qian Shen, Jin-Min Liang, Ming Li, Juan Yu, Shao-Ming Fei
- Abstract summary: We provide a nonlinear improvement of any entanglement witness for $2otimes d$ quantum systems.
The improved separability criterion only needs two more measurements on local observables.
- Score: 6.480747695537184
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: The entanglement witness is an important and experimentally applicable tool
for entanglement detection. In this paper, we provide a nonlinear improvement
of any entanglement witness for $2\otimes d$ quantum systems. Compared with any
existing entanglement witness, the improved separability criterion only needs
two more measurements on local observables. Detailed examples are employed to
illustrate the efficiency of the nonlinear improvement for general, optimal and
non-decomposable entanglement witnesses.
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