Off-diagonal quantum holonomy along density operators
نویسنده
چکیده
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.
منابع مشابه
ua nt - p h / 04 03 20 4 v 1 2 9 M ar 2 00 4 Off - diagonal quantum holonomy along density operators
Uhlmann’s concept of quantum holonomy for paths of density operators is generalised to the off-diagonal case. This generalisation may provide information about the subjacent geometry of the space of density operators when the Uhlmann holonomy is undefined. Comparison with previous definitions of off-diagonal geometric phases for pure and mixed states is carried out. PACS numbers: 03.65.Vf ‡ Ele...
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