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arXiv · 2403.04813

Exploring the Non-Markovian Dynamics in Depolarizing Maps

Ali Abu-Nada·Subhashish Banerjee·Vivek Balasaheb Sabale
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Abstract

The non-Markovian depolarizing channel is explored from the perspective of understanding its non-Markovian behavior as well as the occurrence of singularities. The study brings together the various ways to identify and quantify non-Markovianity. This includes dynamical techniques such as quantum information backflow witness, Breuer-Laine-Piilo, Rivas-Huelga-Plenio and Hall- Cresser-Li-Andersson measures. In addition, geometrical visualization of non-Markovian effects is presented using the variation in the volume of accessible states during dynamical evolution. Further, a trajectory-based visualization of the dynamical map within the parameter space is presented. The trajectories traced during evolution demonstrate the loss of CP divisibility and the emergence of non-Markovianity under systematic variations of the system parameters. The effects of increasing system dimensions and qubit numbers on singularity and non-Markovianity are presented, with an extension of characterization techniques to higher-dimensional systems.

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Ali Abu-Nada, Subhashish Banerjee, Vivek Balasaheb Sabale. 2025-03-04. Exploring the Non-Markovian Dynamics in Depolarizing Maps. https://doi.org/10.1103/physreva.110.052209

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