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Off-diagonal mixed state phases in unitary evolution

Erik Sjöqvist·Stefan Filipp
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Abstract

Off-diagonal mixed state phases based upon a concept of orthogonality adapted to unitary evolution and a proper normalisation condition are introduced. Some particular instances are analysed and parallel transport leading to the off-diagonal mixed state geometric phase is delineated. A complete experimental realisation of the off-diagonal mixed state geometric phases in the qubit case using polarisation-entangled two-photon interferometry is proposed.

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Erik Sjöqvist, Stefan Filipp. 2002-12-19. Off-diagonal mixed state phases in unitary evolution. https://arxiv.org/abs/quant-ph/0212111

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