Phase diagram for the one-way quantum deficit of two-qubit X states

  title={Phase diagram for the one-way quantum deficit of two-qubit X states},
  author={Mikhail A. Yurischev},
  journal={Quantum Information Processing},
  • M. Yurischev
  • Published 10 April 2018
  • Physics
  • Quantum Information Processing
The one-way quantum deficit, a measure of quantum correlation, can exhibit for X quantum states the regions (subdomains) with the phases $$\varDelta _0$$Δ0 and $$\varDelta _{\pi /2}$$Δπ/2 which are characterized by constant (i.e., universal) optimal measurement angles, correspondingly, zero and $$\pi /2$$π/2 with respect to the z-axis and a third phase $$\varDelta _\vartheta $$Δϑ with the variable (state-dependent) optimal measurement angle $$\vartheta $$ϑ. We build the complete phase diagram… 
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