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Characterization of pure quantum states of multiple qubits using the Groverian entanglement measure

Yishai Shimoni·Daniel Shapira·Ofer Biham
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Abstract

The Groverian entanglement measure, G(psi), is applied to characterize a variety of pure quantum states |psi> of multiple qubits. The Groverian measure is calculated analytically for certain states of high symmetry, while for arbitrary states it is evaluated using a numerical procedure. In particular, it is calculated for the class of Greenberger-Horne-Zeilinger states, the W states as well as for random pure states of n qubits. The entanglement generated by Grover's algorithm is evaluated by calculating G(psi) for the intermediate states that are obtained after t Grover iterations, for various initial states and for different sets of the marked states.

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Yishai Shimoni, Daniel Shapira, Ofer Biham. 2003-09-07. Characterization of pure quantum states of multiple qubits using the Groverian entanglement measure. https://doi.org/10.1103/physreva.69.062303

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