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Off-diagonal quantum holonomy along density operators

Stefan Filipp·Erik Sjöqvist
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Abstract

Uhlmann's concept of quantum holonomy for paths of density operators is generalised to the off-diagonal case providing insight into the geometry of state space when the Uhlmann holonomy is undefined. Comparison with previous off-diagonal geometric phase definitions is carried out and an example comprising the transport of a Bell-state mixture is given.

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Stefan Filipp, Erik Sjöqvist. 2005-04-28. Off-diagonal quantum holonomy along density operators. https://doi.org/10.1016/j.physleta.2005.05.043

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