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arXiv · 1302.1783

Quantum Channel Negativity as a Measure of System-Bath Coupling and Correlation

James M. McCracken
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Abstract

Complete positivity is a ubiquitous assumption in the study of quantum systems interacting with the environment, but the lack of complete positivity of a quantum evolution (called the "negativity") can be used as a measure of the system-bath coupling and correlation. The negativity can be computed from the Choi representation of a channel, is always defined and bounded, and can be used to understand environmentally induced noise in a quantum system.

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James M. McCracken. 2013-09-10. Quantum Channel Negativity as a Measure of System-Bath Coupling and Correlation. https://doi.org/10.1103/physreva.88.032103

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