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arXiv · 0803.3311

Three-Qubit Groverian Measure

Eylee Jung·Mi-Ra Hwang·DaeKil Park·Levon Tamaryan·Sayatnova Tamaryan
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Abstract

The Groverian measures are analytically computed in various types of three-qubit states. The final results are also expressed in terms of local-unitary invariant quantities in each type. This fact reflects the manifest local-unitary invariance of the Groverian measure. It is also shown that the analytical expressions for various types have correct limits to other types. For some types (type 4 and type 5) we failed to compute the analytical expression of the Groverian measure in this paper. However, from the consideration of local-unitary invariants we have shown that the Groverian measure in type 4 should be independent of the phase factor $ϕ$, which appear in the three-qubit state $|ψ>$. This fact with geometric interpretation on the Groverian measure may enable us to derive the analytical expressions for general arbitrary three-qubit states in near future.

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Eylee Jung, Mi-Ra Hwang, DaeKil Park, Levon Tamaryan, Sayatnova Tamaryan. 2008-05-30. Three-Qubit Groverian Measure. https://arxiv.org/abs/0803.3311

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