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arXiv · quant-ph/0701025

Probabilistic reversing operation with fidelity and purity gain for macroscopic quantum superposition

Hiroaki Terashima·Masahito Ueda
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Abstract

It is shown that a large class of weak disturbances on macroscopic quantum superpositions can be canceled by a probabilistic reversing operation on the system. We illustrate this for spin systems undergoing an Ising-type interaction with the environment and demonstrate that both the fidelity to the original state and the purity of the amended state can simultaneously be increased by the reversing operation. A possible experimental scheme to implement our scheme is discussed.

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Hiroaki Terashima, Masahito Ueda. 2007-04-07. Probabilistic reversing operation with fidelity and purity gain for macroscopic quantum superposition. https://doi.org/10.1103/physreva.75.052323

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