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Phase space contraction and quantum operations

Ignacio Garcia-Mata·Marcos Saraceno·Maria Elena Spina·Gabriel Carlo
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Abstract

We give a criterion to differentiate between dissipative and diffusive quantum operations. It is based on the classical idea that dissipative processes contract volumes in phase space. We define a quantity that can be regarded as ``quantum phase space contraction rate'' and which is related to a fundamental property of quantum channels: non-unitality. We relate it to other properties of the channel and also show a simple example of dissipative noise composed with a chaotic map. The emergence of attaractor-like structures is displayed.

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Ignacio Garcia-Mata, Marcos Saraceno, Maria Elena Spina, Gabriel Carlo. 2005-08-25. Phase space contraction and quantum operations. https://doi.org/10.1103/physreva.72.062315

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