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Direct measurement of concurrence for atomic two-qubit pure states

G. Romero·C. E. Lopez·F. Lastra·E. Solano·J. C. Retamal
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Abstract

We propose a general scheme to measure the concurrence of an arbitrary two-qubit pure state in atomic systems. The protocol is based on one- and two-qubit operations acting on two available copies of the bipartite system, and followed by a global qubit readout. We show that it is possible to encode the concurrence in the probability of finding all atomic qubits in the ground state. Two possible scenarios are considered: atoms crossing 3D microwave cavities and trapped ion systems.

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G. Romero, C. E. Lopez, F. Lastra, E. Solano, J. C. Retamal. 2006-11-01. Direct measurement of concurrence for atomic two-qubit pure states. https://doi.org/10.1103/physreva.75.032303

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