Impact of positivity and complete positivity on accessibility of Markovian dynamics

نویسنده

Raffaele Romano

چکیده

We consider a two-dimensional quantum control system evolving under an entropyincreasing irreversible dynamics in the semigroup form. Considering a phenomenological approach to the dynamics, we show that the accessibility property of the system depends on whether its evolution is assumed to be positive or completely positive. In particular, we characterize the family of maps having different accessibility and show the impact of that property on observable quantities by means of a simple physical model.

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