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arXiv · 1212.4584

Resources needed for non-unitary quantum operations

Raam Uzdin
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Abstract

Non-unitary operations generated by an effective non-Hermitian Hamiltonian can be used to create quantum state manipulations which are impossible in Hermitian quantum mechanics. These operations include state preparation (or cooling) and non-orthogonal state discrimination. In this work we put a lower bound on the resources needed for the construction of some given non-unitary evolution. Passive systems are studied in detail and a general feature of such a system is derived. After interpreting our results using the singular value decomposition, several examples are studied analytically. In particular, we put a lower bound on the resources needed for non-Hermitian state preparation and non-orthogonal state discrimination.

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Raam Uzdin. 2012-12-19. Resources needed for non-unitary quantum operations. https://doi.org/10.1088/1751-8113/46/14/145302

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