Abstract
We experimentally explore the state space of three qubits on a nuclear magnetic resonance (NMR) quantum-information processor. We construct a scheme to experimentally realize a canonical form for general three-qubit states up to single-qubit unitaries. This form involves a nontrivial combination of Greenberger-Horne-Zeilinger (GHZ) and -type maximally entangled states of three qubits. The general circuit that we have constructed for the generic state reduces to those for GHZ and states as special cases. The experimental construction of a generic state is carried out for a nontrivial set of parameters and the good fidelity of preparation is confirmed by complete state tomography. The GHZ and states are constructed as special cases of the general experimental scheme. Further, we experimentally demonstrate a curious fact about three-qubit states, where for almost all pure states, the two-qubit reduced states can be used to reconstruct the full three-qubit state. For the case of a generic state and for the state, we demonstrate this method of reconstruction by comparing it to the directly tomographed three-qubit state.
2 More- Received 13 July 2014
- Revised 19 December 2014
DOI:https://doi.org/10.1103/PhysRevA.91.022312
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