# Multipartite quantum and classical correlations in symmetric n-qubit mixed states

@article{Giorgi2014MultipartiteQA, title={Multipartite quantum and classical correlations in symmetric n-qubit mixed states}, author={Gian Luca Giorgi and Steve Campbell}, journal={Quantum Information Processing}, year={2014}, volume={15}, pages={4599-4611} }

We discuss how to calculate genuine multipartite quantum and classical correlations in symmetric, spatially invariant, mixed n-qubit density matrices. We show that the existence of symmetries greatly reduces the amount of free parameters to be optimized in order to find the optimal measurement that minimizes the conditional entropy in the discord calculation. We apply this approach to the states exhibited dynamically during a thermodynamic protocol to extract maximum work. We also apply the…

## 3 Citations

### Analytical expression of genuine tripartite quantum discord for symmetrical X-states

- PhysicsQuantum Inf. Process.
- 2015

An analytical expression of GTQD for three-qubit systems characterized by a subclass of symmetrical X-states is derived and it is believed that the procedure here developed constitutes a valid guideline to investigate quantum correlations in form of discord in more general multipartite systems.

### Maximally genuine multipartite entangled mixed X-states of N-qubits

- Mathematics
- 2015

For every possible spectrum of 2 N ?> -dimensional density operators, we construct an N-qubit X-state of the same spectrum and maximal genuine multipartite (GM-) concurrence, hence characterizing a…

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