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arXiv · 2202.07674

Decimation technique for open quantum systems: a case study with driven-dissipative bosonic chains

Álvaro Gómez-León·Tomás Ramos·Diego Porras·Alejandro González-Tudela
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Abstract

The unavoidable coupling of quantum systems to external degrees of freedom leads to dissipative (non-unitary) dynamics, which can be radically different from closed-system scenarios. Such open quantum system dynamics is generally described by Lindblad master equations, whose dynamical and steady-state properties are challenging to obtain, especially in the many-particle regime. Here, we introduce a method to deal with these systems based on the calculation of (dissipative) lattice Green's function with a real-space decimation technique. Compared to other methods, such technique enables obtaining compact analytical expressions for the dynamics and steady-state properties, such as asymptotic decays or correlation lengths. We illustrate the power of this method with several examples of driven-dissipative bosonic chains of increasing complexity, including the Hatano-Nelson model. The latter is especially illustrative because its surface and bulk dissipative behavior are linked due to its non-trivial topology, which manifests in directional amplification.

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Álvaro Gómez-León, Tomás Ramos, Diego Porras, Alejandro González-Tudela. 2022-02-15. Decimation technique for open quantum systems: a case study with driven-dissipative bosonic chains. https://doi.org/10.1103/physreva.105.052223

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