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arXiv · 2412.08724

Separability Lindblad equation for dynamical open-system entanglement

Julien Pinske·Laura Ares·Benjamin Hinrichs·Martin Kolb·Jan Sperling
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Abstract

Providing entanglement for the design of quantum technologies in the presence of noise constitutes today's main challenge in quantum information science. A framework is required that assesses the build-up of entanglement in realistic settings. In this work, we put forth a new class of nonlinear quantum master equations in Lindblad form that unambiguously identify dynamical entanglement in open quantum systems via deviations from a separable evolution. This separability Lindblad equation restricts quantum trajectories to classically correlated states only. Unlike many conventional approaches, here the entangling capabilities of a process are not characterized by input-output relations, but separability is imposed at each instant of time. We solve these equations for crucial examples, thereby quantifying the dynamical impact of entanglement in non-equilibrium scenarios. Our results allow to benchmark the engineering of entangled states through dissipation. The separability Lindblad equation provides a unique path to characterizing quantum correlations caused by arbitrary system-bath interactions, specifically tailored for the noisy intermediate-scale quantum era.

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Julien Pinske, Laura Ares, Benjamin Hinrichs, Martin Kolb, Jan Sperling. 2024-12-11. Separability Lindblad equation for dynamical open-system entanglement. https://doi.org/10.1103/kd3b-bfxq

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