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arXiv · 2111.11300

Entanglement transitions in the quantum Ising chain: A comparison between different unravelings of the same Lindbladian

Giulia Piccitto·Angelo Russomanno·Davide Rossini
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Abstract

We study the dynamics of entanglement in the quantum Ising chain with dephasing dissipation in a Lindblad master equation form. We consider two unravelings which preserve the Gaussian form of the state, allowing to address large system sizes. The first unraveling gives rise to a quantum-state-diffusion dynamics, while the second one describes a specific form of quantum-jump evolution, suitably constructed to preserve Gaussianity. In the first case we find a crossover from area-law to logarithm-law entanglement scaling and draw the related phase diagram. In the second case we only find logarithm-law scaling, remarking the different entanglement behavior for different unravelings of the same Lindblad equation. Finally, we compare these outcomes with the predictions of a non-Hermitian Hamiltonian evolution, finding conflicting results.

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Giulia Piccitto, Angelo Russomanno, Davide Rossini. 2021-11-22. Entanglement transitions in the quantum Ising chain: A comparison between different unravelings of the same Lindbladian. https://doi.org/10.1103/physrevb.105.064305

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