Off-diagonal Mixed State Phases in Unitary Evolution A
نویسنده
چکیده
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 polarisationentangled two-photon interferometry is proposed.
منابع مشابه
ar X iv : q ua nt - p h / 03 07 01 2 v 2 22 O ct 2 00 3 Off - diagonal generalization of the mixed state geometric phase
The concept of off-diagonal geometric phases for mixed quantal states in unitary evolution is developed. We show that these phases arise from three basic ideas: (1) fulfillment of quantum parallel transport of a complete basis, (2) a concept of mixed state orthogonality adapted to unitary evolution, and (3) a normalization condition. We provide a method for computing the off-diagonal mixed stat...
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