Uhlmann phase in composite systems with entanglement

  title={Uhlmann phase in composite systems with entanglement},
  author={Jorge Villavicencio and Ernesto Cota and Fernando Rojas and Jes'us A. Maytorena and Daniel Galindo},
  journal={Physical Review A},
We study the geometric Uhlmann phase of entangled mixed states in a composite system made of two coupled spin1 2 particles with a magnetic field acting on one of them. Within a depolarizing channel setup, an exact analytical expression for such a phase in each subsystem is derived. We find an explicit connection to the concurrence of the depolarizing channel density matrix, which allows to characterize the features of the Uhlmann phase in terms of the degree of entanglement in the system. In… 

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