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arXiv quant-ph/04050482004-05quant-ph

Kinematic approach to off-diagonal geometric phases of nondegenerate and degenerate mixed states

D. M. Tong, Erik Sjöqvist, Stefan Filipp, L. C. Kwek, C. H. Oh

备注：: New section IV, new figure, journal ref added
发表信息：: Phys. Rev. A 71, 032106 (2005)
DOI：: 10.1103/PhysRevA.71.032106

英文摘要：

Off-diagonal geometric phases have been developed in order to provide information of the geometry of paths that connect noninterfering quantal states. We propose a kinematic approach to off-diagonal geometric phases for pure and mixed states. We further extend the mixed state concept proposed in [Phys. Rev. Lett. {\bf 90}, 050403 (2003)] to degenerate density operators. The first and second order off-diagonal geometric phases are analyzed for unitarily evolving pairs of pseudopure states.

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